MATLAB程序设计教程(第二版)课后答案(可编辑修改word版)
(完整word版)MATLAB程序设计教程(第二版)课后答案
MATLAB第二版课后答案unit3—8 unit3实验指导1、 n=input（'请输入一个三位数：'）;a=fix（n/100)；b=fix（（n-a*100)/10）；c=n-a＊100-b＊10；d=c＊100+b*10+a2（1）n=input('请输入成绩’）；switch ncase num2cell（90：100)p='A'；case num2cell（80:89)p='B'；case num2cell(70：79）p=’C';case num2cell（60:69)p='D'；otherwisep='E';endprice=p(2）n=input(’请输入成绩');if n〉=90&n〈=100p='A’；elseif n>=80&n<=89p='B';elseif n〉=70&n<=79p=’C’;elseif n>=60＆n<=69p='D'；elsep='E'；endprice=p(3）tryn;catchprice='erroe'end3n=［1,5,56，4,3,476，45，6，3，76，45,6,4,3，6，4,23,76,908，6]; a=n(1);b=n(1)；for m=2:20if n（m）>aa=n（m）；elseif n（m)<bb=n（m）;endendmax=amin=b法2n=[1,5，56,4，3，476,45，6,3,76,45，6，4，3,6，4，23，76,908,6］;min=min(n)max=max(n）4b=［—3.0:0.1:3.0];for n=1：61a=b(n）；y(n)=（exp（0.3＊a)-exp(—0。
matlab程序设计(第二版)课后作业答案
一、实验结果：1、利用函数eye，ones，zeros，rand，randn 函数分别产生首先编写脚本函数如下:a1=eye(3)a2=eye(15,8)b1=ones(3)b2=ones(15,8)c1=zeros(3)c2=zeros(15,8)d1=2*rand(3,3)-1d2=2*randn(3,3)+1r1=2*rand(15,8)-1r2=2*randn(15,8)+12、使用函数diag和reshape函数：编写脚本：a1=[8 -7 2];a2=diag(a1);a3=fliplr(a2);a4=[5 3];a5=diag(a4,-1);a6=fliplr(a5);a=a3+a6a1=reshape(a,1,9)b1=[4 5 7];b2=diag(b1);b3=fliplr(b2);b4=[2 0 8];b5=diag(b4);b=b3+b5b6=reshape(b,1,9)3、直接在工作空间里输入：a=5-round(100*rand(50,2))/104、脚本文件：a=[-pi:2*pi/360:pi];y1=sin(a)y2=cos(a)5.、编写脚本：A=rand(10)b=A>0.6[i,j,v]=find(b)c=sum(v)6、编写脚本：A=randn(10)b=-0.5<A<0.5[i,j,v]=find(b);c=sum(v)7、编写实现表中功能的语句：if and(a<1,b<=0.5)语句1elseif and(a<1,b>0.5)语句2elseif and(a>=1,b<=0.5)语句3elseif and(a>=1,b>0.5)语句4elsedisp('error')end8、编写脚本如下：A=2*rand(3)b=A>1c=A.*b;[i,j,v]=find(c);v9、编写脚本函数：A=101*rand(100,3)b=A>100;c=A.*b;[i,j,d]=find(c);d10、为节约空间，用5*5的矩阵来模拟100*100的矩阵：编写脚本函数如下：A=[0 2 0 3 0;0 0 0 0 0;0 8 0 5 0;0 4 0 5 0;0 4 0 2 0]b=any(A);[i,j,v]=find(1-b);A(:,j)=[];B=A';c=any(B);[i,j,v]=find(1-c);B(:,j)=[];A=B'一、实验结果：1、输入脚本函数：x=0:pi/50:2*pi;k=[1 26 51 76 101];x(k)=[];figure(1)subplot(2,2,1)plot(x,sin(x)),grid onsubplot(2,2,2)plot(x,cos(x)),grid onsubplot(2,2,3)plot(x,tan(x)),grid onsubplot(2,2,4)plot(x,cot(x)),grid on2、分别利用title函数给图形加上标题，用text函数给坐标系中的建立文本对象，可将字符串放在图形的指定位置，用xlabel、ylabel函数添加x、y轴的标记，用legend 函数给图形加上插图说明。
MATLAB程序设计教程课后答案.doc
MATLAB第二版课后答案unit3-8 unit3实验指导1、 n=input('请输入一个三位数：');a=fix(n/100);b=fix((n-a*100)/10);c=n-a*100-b*10;d=c*100+b*10+a2（ 1）n=input(' 请输入成绩 ');switch ncase num2cell(90:100)p='A';case num2cell(80:89)p='B';case num2cell(70:79)p='C';case num2cell(60:69)p='D';otherwisep='E';endprice=p（2） n=input(' 请输入成绩 '); ifn>=90&n<=100p='A';elseif n>=80&n<=89p='B';elseif n>=70&n<=79p='C';elseif n>=60&n<=69p='D';elsep='E';endprice=p（3）try n;catchprice='erroe'end3n=[1,5,56,4,3,476,45,6,3,76,45,6,4,3,6,4,23,76,908,6];a=n(1) ；b=n(1);for m=2:20if n(m)>aa=n(m);elseif n(m)<bb=n(m);endendmax=amin=b法2n=[1,5,56,4,3,476,45,6,3,76,45,6,4,3,6,4,23,76,908,6];min=min(n)max=max(n)4b=[::];for n=1:61a=b(n);y(n)=(exp*a)-exp*a))/2*sin(a++log(+a)/2);endy5y1=0;y2=1;n=input(' 请输入 n 的值： ');for i=1:ny1=y1+1/i^2;y2=y2*((4*i*i)/((2*i-1)*(2*i+1)));endy1y26A=[1,1,1,1,1,1;2,2,2,2,2,2;3,3,3,3,3,3;4,4,4,4,4,4;5,5,5,5,5,5;6,6,6,6,6,6]; n=input(' 请输入 n 的值 :');if n<=5&n>=0disp(A([n],:));elseif n<0disp(lasterr);else disp(A([6],:));disp(lasterr);end7（ 1）f=[];for n=1:40f(n)=n+10*log(n^2+5);endy=f(40)/(f(30)+f(20))（2）f=[];a=0;for n=1:40f(n)=a+n*(n+1);a=f(n);endy=f(40)/(f(30)+f(20))8y=0;m=input('输入m的值:');n=input(' 输入 n 值： ');for i=1:ny=y+i^m;endy************************************************************ function s=shi8_1(n,m)s=0;for i=1:ns=s+i^m;end************************************************************ shi8_1(100,1)+shi8_1(50,2)+shi8_1(10,1/2)思考练习2N=[1,2,3,4,5];2.*NN./21./N1./N.^23s=fix(100*rand(1,20)*9/10+10)y=sum(s)/20j=0;for i=1:20if s(i)<y&rem(s(i),2)==0j=j+1;A(j)=s(i);else continue;endendA4y1=0;y2=0;n=input(' 请输入 n 的值： '); for i=1:ny1=y1+-(-1)^i/(2*i-1);y2=y2+1/4^i;endy1y2unit4实验指导1（ 1）x=-10::10;y=x-x.^3./6;plot(x,y)（2）x=-10::10;ezplot('x^2+2*y^2-64',[-8,8]); grid on;2t=-pi:pi/10:pi;y=1./(1+exp(-t));subplot(2,2,1);bar(t,y);title('条形图 (t,y)');axis([-pi,pi,0,1]);subplot(2,2,2);stairs(t,y,'b');title('阶梯图 (t,y)');axis([-pi,pi,0,1]);subplot(2,2,3);stem(t,y,'k');title('杆图 (t,y)');axis([-pi,pi,0,1]);subplot(2,2,4);loglog(t,y,'y');title('对数坐标图 (t,y)');3（ 1）t=0:pi/50:2*pi;r=5.*cos(t)+4;polar(t,r);title('\rho=5*cos\theta+4'); （2）t=-pi/3:pi/50:pi/3;r=5.*((sin(t)).^2)./cos(t); polar(t,r);4（ 1）t=0:pi/50:2*pi;x=exp(-t./20).*cos(t);y=exp(-t./20).*sin(t);z=t;plot3(x,y,z);grid on;（2）[x,y]=meshgrid(-5:5);z=zeros(11)+5;mesh(x,y,z);shading interp;5[x,y,z]=sphere(20);surf(x,y,z);axis off;shading interp;m=moviein(20);for i=1:20axis([-i,i,-i,i,-i,i])m(:,i)=getframe;endmovie(m,4);思考练习2（ 1）x=-5::5;y=(1./(2*pi)).*exp((-(x.^2))/2); plot(x,y);（2）t=-2*pi::2*pi;x=t.*sin(t);y=t.*cos(t);plot(x,y);grid on;3t=0:pi/1000:pi;x=sin(3.*t).*cos(t);y1=sin(3.*t).*sin(t);y2=2.*;plot(x,y1,'k',x,y2);hold on;k=find(abs(y1-y2)<1e-2);x1=x(k);y3=2.*;plot(x1,y3,'rp');4x=-2::2;y=sin(1./x);subplot(2,1,1);plot(x,y);subplot(2,1,2);fplot('sin(1./x)',[-2,2],1e-4);5（ 1）i=-4*pi::10;j=12./sqrt(i);polar(i,j);title('{\rho}=12/sqrt(\theta)')（2）a=-pi/6::pi/6;b=3.*asin(a).*cos(a)./((sin(a)).^3+(cos(a)).^3); polar(a,b);6（ 1）[u,v]=meshgrid(-4::4);x=3.*u.*sin(v);y=2.*u.*cos(v);z=4.*u.^2;subplot(2,1,1);mesh(x,y,z);subplot(2,1,2);surf(x,y,z);（2）[x,y]=meshgrid(-3::3);z=-5./(1+x.^2+y.^2);subplot(1,2,1);mesh(x,y,z);subplot(1,2,2);surf(x,y,z);unit5实验指导1A=randn(10,5)x=mean(A)y=std(A)Max=max(max(A))Min=min(min(A))Sumhang=sum(A,2)SumA=sum(Sumhang)B=sort(A);C=sort(B,2,'descend');C2（ 1）a=0:15:90;b=a./180.*pi;s=sin(b)c=0:15:75;d=c./180.*pi;t=tan(d)e=input(' 请输入想计算的值：'); S=sin(e/180*pi)T=tan(e/180*pi)S1=interp1(a,s,e,'spline')T1=interp1(c,t,e,'spline')P1=polyfit(a,s,5);P2=polyfit(c,t,5);S2=polyval(P1,e)T2=polyval(P2,e)（2）n=[1,9,16,25,36,49,64,81,100];N=sqrt(n);x=input('ji suan zhi : ');interp1(n,N,x,'cubic')3N=64;T=5;t=linspace(0,T,N);h=exp(-t);dt=t(2)-t(1);f=1/dt;X=fft(t);F=X(1:N/2+1);f=f*(0:N/2)/N;plot(f,abs(F),'-*')4P=[2,-3,0,5,13];Q=[1,5,8];p=polyder(P)q=polyder(P,Q)[a,b]=polyder(P,Q)5P1=[1,2,4,0,5];P2=[0,1,2];P3=[1,2,3];P=P1+conv(P2,P3)X=roots(P)A=[-1,,;,2,;0,5,];p=polyval(P,A)思考练习4A=rand(1,30000);a=mean(A)b=std(A)Max=max(A)Min=min(A)n=0;for i=1:30000if(A(i)>n=n+1;endendny=n/300005p=[45,74,54,55,14;78,98,45,74,12;87,98,85,52,65] [M,S]=max(p)[N,H]=min(p)junzhi=mean(p,1)fangcha=std(p,1,1)zong=sum(p,2);[Max,wei]=max(zong)[Min,wei]=min(zong)[zcj,xsxh]=sort(zong,'descend')6x=[1:10:101];y=[0,,,,,,,,,,];[p,s]=polyfit(x,y,5)a=1:5:101;y1=polyval(p,a);plot(x,y,':o',a,y1,'-*')unit6实验指导1A=[1/2,1/3,1/4;1/3,1/4,1/5;1/4,1/5,1/6];p=[,,]';x=A\pA=[1/2,1/3,1/4;1/3,1/4,1/5;1/4,1/5,1/6]; p=[,,]';x=A\pcond(A)2（ 1）x1=fzero(@funx1,-1)function fx=funx1(x)fx=x^41+x^3+1;（2）x2=fzero(@funx2,function fx=funx2(x)fx=x-sin(x)/x;（3）options=optimset('Display','off');x=fsolve(@fun3,[1,1,1]',options)q=fun3(x)function q=fun3(p)x=p(1);y=p(2);z=p(3);q(1)=sin(x)+y^2+log(z)-7;q(2)=3*x+2^y-z^3+1;q(3)=x+y+z-5;3（ 1）t0=0;tf=5;y0=1;[t,y]=ode23(@fun4,[t0,tf],y0);t'y'function yp=fun4(t,y)yp=-+sin(10*t))*y;（2）t0=0;tf=5;y0=1;[t,y]=ode23(@fun5,[t0,tf],y0);t'y'function yp=fun5(t,y)yp=cos(t)-y/(1+t^2);4x=fminbnd(@mymin,0,2);-mymin(x)function fx=mymin(x)fx=-(1+x.^2)/(1+x.^4);5options=optimset('Display','off');[x,fval]=fmincon(@fun6,[0,0,0],[],[],a,b,lb,ub)-fvalfunction f=fun6(x)f=-(sqrt(x(1))+(400-x(1))*+(sqrt(x(2))+(400-x(1))*(2))*+sqrt(3)+(((400-x(1) )*(2))*(3))*+sqrt(x(x4)));思考练习1（ 1）A=[2,3,5;3,7,4;1,-7,1];B=[10,3,5]';C1=inv(A)*BC2=A\B[L,U]=lu(A);x=U\(L\B)（2）A=[6,5,-2,5;9,-1,4,-1;3,4,2,-2;3,-9,0,2];B=[-4,13,1,11]';C1=inv(A)*BC2=A\B[L,U]=lu(A);x=U\(L\B)2（ 1）x1=fzero(@funx1,function fx=funx1(x)fx=3*x+sin(x)-exp(x);（2）x1=fzero(@funx2,1)function fx=funx2(x)fx=x-1/x+5;（3）options=optimset('Display','off');x=fsolve(@fun3,[3,0]',options)q=fun3(x)function q=fun3(p)x=p(1);y=p(2);q(1)=x^2+y^2-9;q(2)=x+y-1;3（ 1）t0=0;tf=5;y0=[0,1];[t,y]=ode45(@vdpol,[t0,tf],y0);[t,y]function ydot=vdpol(t,y);ydot(1)=(2-3*y(2)-2*t*y(1))./(1+t^2);ydot(2)=y(1);ydot=ydot';（2）t0=0;tf=5;y0=[1;0;2];[t,y]=ode45(@vdpoll,[t0,tf],y0);[t,y]function ydot=vdpoll(t,y);ydot(1)=cos(t)-y(3)./(3+sin(t))+5*y(1).*cos(2*t)/((t+1).^2)-y(2); ydot(2)=y(1);ydot(3)=y(2);ydot=ydot';4x=fminbnd(@mymin,0,pi);-mymin(x)function fx=mymin(x)fx=-sin(x)-cos(x.^2);5[x,y1]=fminbnd(@mymax,0,;-y1function fx=mymax(x);fx=-(9*x+4*x.^3-12*x.^2);unit7实验指导1（ 1）format longfx=inline('sin(x)./x');[I,n]=quadl(fx,0,2,1e-10)（2）format longfx=inline('1./(.^2+-1./(.^2+-6');2（ 1）global ki;ki=0;I=dblquad(@fxy,0,1,0,1)ki（2）f=inline('abs(cos(x+y))','x','y');I=dblquad(f,0,pi,0,pi)3X=::;F=[,,,,,,];trapz(X,F)4p=0:pi/5:2*pi;for n=1:3nDX=diff(sin(p),n)end5f=inline('sin(x)./(x+cos(2.*x))');g=inline('(cos(x).*(x+cos(2*x))-sin(x).*(1-2.*sin(2*x)))/(x+cos(2.*x)).^2') ;x=-pi::pi;p=polyfit(x,f(x),5);dp=polyder(p);dpx=polyval(dp,x);%dx=diff(f([x,]))/; %直接对gx=g(x);%plot(x,dpx,x,dx,'.',x,gx,'-');%求 dp 在假设点的函数值f(x) 求数值导数求函数 f 的导函数作图g 在假设点的导数思考练习2format longfx=inline('1./(1+x.^2)');[I,n]=quad(fx,-Inf,Inf,1e-10) [I,n]=quadl(fx,-Inf,Inf,1e-10) x=-100000:100000;y=1./(1+x.^2);trapz(x,y)format short3(1)format longfx=inline('log(1+x)./(1+x.^2)');(2)format longfx=inline('sqrt(cos(t.^2)+4*sin((2*t).^2)+1)'); [I,n]=quad(fx,0,2*pi,1e-10)4f=inline('4.*x.*z.*exp(-z.^2.*y-x.^2)');I=triplequad(f,0,pi,0,pi,0,1)5f=inline('sin(x)');g=inline('cos(x)');x=0::2*pi;p=polyfit(x,f(x),5);dp=polyder(p);dpx=polyval(dp,x);dx=diff(f([x,2*pi+]))/;gx=g(x);plot(x,dpx,x,dx,'.',x,gx,'-')unit8实验指导1syms x y;s=x^4-y^4;factor(s)factor(5135)2syms x;f=(x-2)/(x^2-4);limit(f,x,2)sym x;f=(sqrt(pi)-sqrt(acos(x)))/sqrt(x+1);limit(f,x,-1,'right')3sym x;f=sin(1/x);diff(f,'x')diff(f,'x',2)sym x;f=(1-cos(2*x))/x;diff(f,'x')diff(f,'x',2)4sym x;f=sqrt(exp(x)+1);int(f,'x')syms x y;f=x/(x+y);int(f,'y')sym x;f=exp(x)*(1+exp(x))^2;int(f,'x',0,log(2))sym x;f=x*log(x);int(f,'x',1,exp(1))5sym x;s=symsum((-1)^(x+1)/x,1,Inf)sym y;z=symsum(y^(2*y-1)/(2*y-1),1,Inf)6sym x;f1=(exp(x)+exp(-x))/2;f2=sqrt(x^3-2*x+1);taylor(f1,x,5,0)taylor(f2,x,6,0)7syms x y a;x=solve('x^3+a*x+1=0','x')x=solve('sin(x)+2*cos(x)-sqrt(x)=0','x')[x y]=solve('log(x/y)=9','exp(x+y)=3','x','y')8syms n;[x,y]=dsolve('x*(D2y)+(1-n)*(Dy)+y=0','y(0)=0','Dy(0)=0','x') 思考练习2syms x B1 B2 a bs1=2*((cos(x))^2)-(sin(x))^2;s2=sin(B1)*cos(B2)-cos(B1)*sin(B2);s3=sqrt((a+sqrt(a^2-b))/2)+sqrt((a-sqrt(a^2-b))/2); s4=(4*x^2+8*x+3)/(2*x+1);h1=simplify(s1)h2=simplify(s2)h3=simplify(s3)h4=simplify(s4)3syms x a;f=abs(x)/x;limit(f,x,0,'left')f=(x+a/x)^x;limit(f,x,inf)4syms x y mf=sqrt(x+sqrt(x+sqrt(x)));m=diff(f,'x')diff(m,'x')syms x y;f=x+y-sqrt(x^2+y^2);z1=diff(f,x)z2=diff(f,y)5syms x y;f=x+y-sqrt(x^2+y^2);z1=diff(f,x)z2=diff(f,y)sym x;f=1/(asin(x)^2*(1-x^2)^(1/2));int(f)6syms xf=1/(1+x);int(f,0,4)sym x;f=x^3*sin(x)^2/(x^6+2*x^4+1);int(f,-1,1)sym x;f=x^3*sin(x)^2/(x^6+2*x^4+1);int(f,-1,1)7syms ns=symsum(1/4^n,1,inf)sym n;s=symsum(((n+1)/n)^(1/2),1,inf)eval(y)8syms xf=tan(x);taylor(f,x,3,0)syms xf=sin(x)^2;taylor(f,x,5,0)9syms xx=solve('log(1+x)-5/(1+sin(x))=2','x')syms x y z[x y z]=solve('4*x^2/(4*x^2+1)=y','4*y^2/(4*y^2+1)=z','4*z^2/(4*z^2+1)=x','x','y','z')10[x ,y]=dsolve('Dx=3*x+4*y','Dy=5*x-7*y','x(0)=0','y(0)=1','t')。
【免费下载】MATLAB程序设计教程第二版课后答案
end A 4 y1=0;y2=0; n=input('请输入 n 的值：'); for i=1:n
y1=y1+-(-1)^i/(2*i-1); y2=y2+1/4^i; end y1 y2 unit4 实验指导 1（1） x=-10:0.05:10; y=x-x.^3./6; plot(x,y) （2） x=-10:0.5:10; ezplot('x^2+2*y^2-64',[-8,8]); grid on; 2 t=-pi:pi/10:pi; y=1./(1+exp(-t)); subplot(2,2,1);bar(t,y); title('条形图(t,y)'); axis([-pi,pi,0,1]); subplot(2,2,2); stairs(t,y,'b'); title('阶梯图(t,y)'); axis([-pi,pi,0,1]); subplot(2,2,3); stem(t,y,'k'); title('杆图(t,y)'); axis([-pi,pi,0,1]); subplot(2,2,4); loglog(t,y,'y'); title('对数坐标图(t,y)'); 3（1） t=0:pi/50:2*pi; r=5.*cos(t)+4; polar(t,r); title('\rho=5*cos\theta+4'); （2）
p='A'; case num2cell(80:89)
p='B'; case num2cell(70:79)
p='C'; case num2cell(60:69)
(完整word版)MATLAB程序设计与应用第二版课后题答案2
第二章3.设矩阵A为A=[24 23 9 21 6;65 74 24 11 21;34 5 98 75 21;8 42 42 53 121;43 21 45 64 21];（1）B=A(2:5,1:2:5)B =65 24 2134 98 218 42 12143 45 21（2）A(7)=[]A =24 65 34 8 43 23 5 42 21 9 24 98 42 45 21 11 75 53 64 6 21 21 121 21（3）A+30（4）size(A);ndims(A)（5）题目有误（6）reshape(x,3,4)（7）abs(x)（8）char(x)4. L1 =0 0 0 0 1 0 0 0 0L2 =1 1 1 1 1 0 0 0 0L3 =0 0 0 1 1 1 0 0 0L4 =4 5 65.(1)B=A(1:3,:)C=A(:,1:2)D=A(2:4,3:4)E=B*CB =23.0000 10.0000 -0.7780 041.0000 -45.0000 65.0000 5.000032.0000 5.0000 0 32.0000C =23.0000 10.000041.0000 -45.000032.0000 5.00006.0000 -9.5400D =65.0000 5.00000 32.000054.0000 3.1400E =1.0e+003 *0.9141 -0.22391.20802.71231.1330 -0.2103(2)E<Dans =0 10 00 1E&Dans =1 10 11 1E|Dans =1 11 11 1~D|~Eans =0 01 00 0find(A>=10&A<25)ans =156.all(A)ans =any(A)ans =1isnan(A)ans =0 1 0 0 0 0 0isinf(A)ans =0 0 1 1 0 0 0isfinite(A)ans =1 0 0 0 1 1 17.A(1).x1=’学号’;A(1).x2=’姓名’;A(1).x3=’专业’;A(1).x4.x41=’成绩1’;………. A(2).x1=’学号’;A(2).x2=’姓名’;A(2).x3=’专业’;A(2).x4.x41=’成绩1’;………. A(3).x1=’学号’;A(3).x2=’姓名’;A(3).x3=’专业’;A(3).x4.x41=’成绩1’;………. A(4).x1=’学号’;A(4).x2=’姓名’;A(4).x3=’专业’;A(4).x4.x41=’成绩1’;………. A(5).x1=’学号’;A(5).x2=’姓名’;A(5).x3=’专业’;A(5).x4.x41=’成绩1’;……….8.(1)size(B)ans =2 2ndims(B)ans =2(2)B(2)ans =[3x3 doubleB(4)ans ={3x3 cell}(3)B(3)=[]B =[1] [3x3 double] {3x3 cell}B{3}=[]B =[1] [3x3 double] []第三章1.(1)A=eye(3)(2) A=100+100*rand(5,6)(3)A=1+sqrt(0.2)*randn(10,50)(4)B=ones(size(A))(5)A+30*eye(size(A))(6)B=diag(diag(A))2.B=rot90(A)C=rot90(A,-1)3.B=inv(A) ;A的逆矩阵C=det(A) ;A的行列式的值D=A*BE=B*AD=E 因此A与A-1是互逆的。
MATLAB程序设计教程(第二版)课后答案
MATLAB第二版课后答案unit3-8 unit3实验指导1、 n=input('请输入一个三位数：');a=fix(n/100);b=fix((n-a*100)/10);c=n-a*100-b*10;d=c*100+b*10+a2（1）n=input('请输入成绩');switch ncase num2cell(90:100)p='A';case num2cell(80:89)p='B';case num2cell(70:79)p='C';case num2cell(60:69)p='D';otherwisep='E';endprice=p（2）n=input('请输入成绩');if n>=90&n<=100p='A';elseif n>=80&n<=89p='B';elseif n>=70&n<=79p='C';elseif n>=60&n<=69p='D';elsep='E';endprice=p（3）tryn;catchprice='erroe'end3n=[1,5,56,4,3,476,45,6,3,76,45,6,4,3,6,4,23,76,908,6];b=n(1);for m=2:20if n(m)>aa=n(m);elseif n(m)<bb=n(m);endendmax=amin=b法2n=[1,5,56,4,3,476,45,6,3,76,45,6,4,3,6,4,23,76,908,6];min=min(n)max=max(n)4b=[-3.0:0.1:3.0];for n=1:61a=b(n);y(n)=(exp(0.3*a)-exp(-0.3*a))/2*sin(a+0.3)+log((0.3+a)/2);endy5y1=0;y2=1;n=input('请输入n的值：');for i=1:ny1=y1+1/i^2;y2=y2*((4*i*i)/((2*i-1)*(2*i+1)));endy1y26A=[1,1,1,1,1,1;2,2,2,2,2,2;3,3,3,3,3,3;4,4,4,4,4,4;5,5,5,5,5,5;6,6,6,6,6,6]; n=input('请输入n的值:');if n<=5&n>=0disp(A([n],:));elseif n<0disp(lasterr);else disp(A([6],:));disp(lasterr);end7（1）f=[];f(n)=n+10*log(n^2+5);endy=f(40)/(f(30)+f(20))（2）f=[];a=0;for n=1:40f(n)=a+n*(n+1);a=f(n);endy=f(40)/(f(30)+f(20))8y=0;m=input('输入m的值:');n=input('输入n值：');for i=1:ny=y+i^m;endy************************************************************ function s=shi8_1(n,m)s=0;for i=1:ns=s+i^m;end************************************************************ shi8_1(100,1)+shi8_1(50,2)+shi8_1(10,1/2)思考练习2N=[1,2,3,4,5];2.*NN./21./N1./N.^23s=fix(100*rand(1,20)*9/10+10)y=sum(s)/20j=0;for i=1:20if s(i)<y&rem(s(i),2)==0j=j+1;A(j)=s(i);else continue;endendA4y1=0;y2=0;n=input('请输入n的值：'); for i=1:ny1=y1+-(-1)^i/(2*i-1);y2=y2+1/4^i;endy1y2unit4实验指导1（1）x=-10:0.05:10;y=x-x.^3./6;plot(x,y)（2）x=-10:0.5:10;ezplot('x^2+2*y^2-64',[-8,8]); grid on;2t=-pi:pi/10:pi;y=1./(1+exp(-t));subplot(2,2,1);bar(t,y);title('条形图(t,y)');axis([-pi,pi,0,1]);subplot(2,2,2);stairs(t,y,'b');title('阶梯图(t,y)');axis([-pi,pi,0,1]);subplot(2,2,3);stem(t,y,'k');title('杆图(t,y)');axis([-pi,pi,0,1]);subplot(2,2,4);loglog(t,y,'y');title('对数坐标图(t,y)');3（1）t=0:pi/50:2*pi;r=5.*cos(t)+4;polar(t,r);title('\rho=5*cos\theta+4');（2）t=-pi/3:pi/50:pi/3;r=5.*((sin(t)).^2)./cos(t); polar(t,r);4（1）t=0:pi/50:2*pi;x=exp(-t./20).*cos(t);y=exp(-t./20).*sin(t);z=t;plot3(x,y,z);grid on;（2）[x,y]=meshgrid(-5:5);z=zeros(11)+5;mesh(x,y,z);shading interp;5[x,y,z]=sphere(20);surf(x,y,z);axis off;shading interp;m=moviein(20);for i=1:20axis([-i,i,-i,i,-i,i])m(:,i)=getframe;endmovie(m,4);思考练习2（1）x=-5:0.1:5;y=(1./(2*pi)).*exp((-(x.^2))/2); plot(x,y);（2）t=-2*pi:0.1:2*pi;x=t.*sin(t);y=t.*cos(t);plot(x,y);grid on;3t=0:pi/1000:pi;x=sin(3.*t).*cos(t);y1=sin(3.*t).*sin(t);y2=2.*x-0.5;plot(x,y1,'k',x,y2);hold on;k=find(abs(y1-y2)<1e-2);x1=x(k);y3=2.*x1-0.5;plot(x1,y3,'rp');4x=-2:0.01:2;y=sin(1./x);subplot(2,1,1);plot(x,y);subplot(2,1,2);fplot('sin(1./x)',[-2,2],1e-4);5（1）i=-4*pi:0.1:10;j=12./sqrt(i);polar(i,j);title('{\rho}=12/sqrt(\theta)')（2）a=-pi/6:0.01:pi/6;b=3.*asin(a).*cos(a)./((sin(a)).^3+(cos(a)).^3); polar(a,b);6（1）[u,v]=meshgrid(-4:0.1:4);x=3.*u.*sin(v);y=2.*u.*cos(v);z=4.*u.^2;subplot(2,1,1);mesh(x,y,z);subplot(2,1,2);surf(x,y,z);（2）[x,y]=meshgrid(-3:0.2:3);z=-5./(1+x.^2+y.^2);subplot(1,2,1);mesh(x,y,z);subplot(1,2,2);surf(x,y,z);unit5实验指导1A=randn(10,5)x=mean(A)y=std(A)Max=max(max(A))Min=min(min(A))Sumhang=sum(A,2)SumA=sum(Sumhang)B=sort(A);C=sort(B,2,'descend');C2（1）a=0:15:90;b=a./180.*pi;s=sin(b)c=0:15:75;d=c./180.*pi;t=tan(d)e=input('请输入想计算的值：'); S=sin(e/180*pi)T=tan(e/180*pi)S1=interp1(a,s,e,'spline')T1=interp1(c,t,e,'spline')P1=polyfit(a,s,5);P2=polyfit(c,t,5);S2=polyval(P1,e)T2=polyval(P2,e)（2）n=[1,9,16,25,36,49,64,81,100]; N=sqrt(n);x=input('ji suan zhi : ');interp1(n,N,x,'cubic')3N=64;T=5;t=linspace(0,T,N);h=exp(-t);dt=t(2)-t(1);f=1/dt;X=fft(t);F=X(1:N/2+1);f=f*(0:N/2)/N;plot(f,abs(F),'-*')4P=[2,-3,0,5,13];Q=[1,5,8];p=polyder(P)q=polyder(P,Q)[a,b]=polyder(P,Q)5P1=[1,2,4,0,5];P2=[0,1,2];P3=[1,2,3];P=P1+conv(P2,P3)X=roots(P)A=[-1,1.2,-1.4;0.75,2,3.5;0,5,2.5];p=polyval(P,A)思考练习4A=rand(1,30000);a=mean(A)b=std(A)Max=max(A)Min=min(A)n=0;for i=1:30000if(A(i)>0.5)n=n+1;endendny=n/300005p=[45,74,54,55,14;78,98,45,74,12;87,98,85,52,65][M,S]=max(p)[N,H]=min(p)junzhi=mean(p,1)fangcha=std(p,1,1)zong=sum(p,2);[Max,wei]=max(zong)[Min,wei]=min(zong)[zcj,xsxh]=sort(zong,'descend')6x=[1:10:101];y=[0,1.0414,1.3222,1.4914,1.6128,1.7076,1.7853,1.8513,1.9085,1.9590,2.0043]; [p,s]=polyfit(x,y,5)a=1:5:101;y1=polyval(p,a);plot(x,y,':o',a,y1,'-*')unit6实验指导1A=[1/2,1/3,1/4;1/3,1/4,1/5;1/4,1/5,1/6];p=[0.95,0.67,0.52]';x=A\pA=[1/2,1/3,1/4;1/3,1/4,1/5;1/4,1/5,1/6]; p=[0.95,0.67,0.53]';x=A\pcond(A)2（1）x1=fzero(@funx1,-1)function fx=funx1(x)fx=x^41+x^3+1;（2）x2=fzero(@funx2,0.5)function fx=funx2(x)fx=x-sin(x)/x;（3）options=optimset('Display','off');x=fsolve(@fun3,[1,1,1]',options)q=fun3(x)function q=fun3(p)x=p(1);y=p(2);z=p(3);q(1)=sin(x)+y^2+log(z)-7;q(2)=3*x+2^y-z^3+1;q(3)=x+y+z-5;3（1）t0=0;tf=5;y0=1;[t,y]=ode23(@fun4,[t0,tf],y0);t'y'function yp=fun4(t,y)yp=-(1.2+sin(10*t))*y;（2）t0=0;tf=5;y0=1;[t,y]=ode23(@fun5,[t0,tf],y0);t'y'function yp=fun5(t,y)yp=cos(t)-y/(1+t^2);4x=fminbnd(@mymin,0,2);-mymin(x)function fx=mymin(x)fx=-(1+x.^2)/(1+x.^4);5options=optimset('Display','off');[x,fval]=fmincon(@fun6,[0,0,0],[],[],a,b,lb,ub)-fvalfunction f=fun6(x)f=-(sqrt(x(1))+(400-x(1))*1.1+(sqrt(x(2))+(400-x(1))*1.1-x(2))*1.1+sqrt(3)+(((400-x(1))*1.1-x(2))*1.1-x(3))*1.1+sqrt(x(x4)));思考练习1（1）A=[2,3,5;3,7,4;1,-7,1];B=[10,3,5]';C1=inv(A)*BC2=A\B[L,U]=lu(A);x=U\(L\B)（2）A=[6,5,-2,5;9,-1,4,-1;3,4,2,-2;3,-9,0,2];B=[-4,13,1,11]';C1=inv(A)*BC2=A\B[L,U]=lu(A);x=U\(L\B)2（1）x1=fzero(@funx1,1.5)function fx=funx1(x)fx=3*x+sin(x)-exp(x);（2）x1=fzero(@funx2,1)function fx=funx2(x)fx=x-1/x+5;（3）options=optimset('Display','off');x=fsolve(@fun3,[3,0]',options)q=fun3(x)function q=fun3(p)x=p(1);y=p(2);q(1)=x^2+y^2-9;q(2)=x+y-1;3（1）t0=0;tf=5;y0=[0,1];[t,y]=ode45(@vdpol,[t0,tf],y0);[t,y]function ydot=vdpol(t,y);ydot(1)=(2-3*y(2)-2*t*y(1))./(1+t^2);ydot(2)=y(1);ydot=ydot';（2）t0=0;tf=5;y0=[1;0;2];[t,y]=ode45(@vdpoll,[t0,tf],y0);[t,y]function ydot=vdpoll(t,y);ydot(1)=cos(t)-y(3)./(3+sin(t))+5*y(1).*cos(2*t)/((t+1).^2)-y(2); ydot(2)=y(1);ydot(3)=y(2);ydot=ydot';4x=fminbnd(@mymin,0,pi);-mymin(x)function fx=mymin(x)fx=-sin(x)-cos(x.^2);5[x,y1]=fminbnd(@mymax,0,1.5);-y1function fx=mymax(x);fx=-(9*x+4*x.^3-12*x.^2);unit7实验指导1（1）format longfx=inline('sin(x)./x');[I,n]=quadl(fx,0,2,1e-10)（2）format longfx=inline('1./((x-0.3).^2+0.01)-1./((x-0.9).^2+0.04)-6');[I,n]=quad(fx,0,1,1e-10)2（1）global ki;ki=0;I=dblquad(@fxy,0,1,0,1)ki（2）f=inline('abs(cos(x+y))','x','y');I=dblquad(f,0,pi,0,pi)3X=0.3:0.2:1.5;F=[0.3895,0.6598,0.9147,1.1611,1.3971,1.6212,1.8325];trapz(X,F)4p=0:pi/5:2*pi;for n=1:3nDX=diff(sin(p),n)end5f=inline('sin(x)./(x+cos(2.*x))');g=inline('(cos(x).*(x+cos(2*x))-sin(x).*(1-2.*sin(2*x)))/(x+cos(2.*x)).^2');x=-pi:0.01:pi;p=polyfit(x,f(x),5);dp=polyder(p);dpx=polyval(dp,x); %求dp在假设点的函数值dx=diff(f([x,3.01]))/0.01; %直接对f(x)求数值导数gx=g(x); %求函数f的导函数g在假设点的导数plot(x,dpx,x,dx,'.',x,gx,'-'); %作图思考练习2format longfx=inline('1./(1+x.^2)');[I,n]=quad(fx,-Inf,Inf,1e-10)[I,n]=quadl(fx,-Inf,Inf,1e-10)x=-100000:100000;y=1./(1+x.^2);trapz(x,y)format short3(1)format longfx=inline('log(1+x)./(1+x.^2)');[I,n]=quad(fx,0,1,1e-10)(2)format longfx=inline('sqrt(cos(t.^2)+4*sin((2*t).^2)+1)'); [I,n]=quad(fx,0,2*pi,1e-10)4f=inline('4.*x.*z.*exp(-z.^2.*y-x.^2)');I=triplequad(f,0,pi,0,pi,0,1)5f=inline('sin(x)');g=inline('cos(x)');x=0:0.01:2*pi;p=polyfit(x,f(x),5);dp=polyder(p);dpx=polyval(dp,x);dx=diff(f([x,2*pi+0.01]))/0.01;gx=g(x);plot(x,dpx,x,dx,'.',x,gx,'-')unit8实验指导1syms x y;s=x^4-y^4;factor(s)factor(5135)2syms x;f=(x-2)/(x^2-4);limit(f,x,2)sym x;f=(sqrt(pi)-sqrt(acos(x)))/sqrt(x+1);limit(f,x,-1,'right')3sym x;f=sin(1/x);diff(f,'x')diff(f,'x',2)sym x;f=(1-cos(2*x))/x;diff(f,'x')diff(f,'x',2)4sym x;f=sqrt(exp(x)+1);int(f,'x')syms x y;f=x/(x+y);int(f,'y')sym x;f=exp(x)*(1+exp(x))^2;int(f,'x',0,log(2))sym x;f=x*log(x);int(f,'x',1,exp(1))5sym x;s=symsum((-1)^(x+1)/x,1,Inf)sym y;z=symsum(y^(2*y-1)/(2*y-1),1,Inf)6sym x;f1=(exp(x)+exp(-x))/2;f2=sqrt(x^3-2*x+1);taylor(f1,x,5,0)taylor(f2,x,6,0)7syms x y a;x=solve('x^3+a*x+1=0','x')x=solve('sin(x)+2*cos(x)-sqrt(x)=0','x')[x y]=solve('log(x/y)=9','exp(x+y)=3','x','y')8syms n;[x,y]=dsolve('x*(D2y)+(1-n)*(Dy)+y=0','y(0)=0','Dy(0)=0','x')思考练习2syms x B1 B2 a bs1=2*((cos(x))^2)-(sin(x))^2;s2=sin(B1)*cos(B2)-cos(B1)*sin(B2);s3=sqrt((a+sqrt(a^2-b))/2)+sqrt((a-sqrt(a^2-b))/2); s4=(4*x^2+8*x+3)/(2*x+1);h1=simplify(s1)h2=simplify(s2)h3=simplify(s3)h4=simplify(s4)3syms x a;f=abs(x)/x;limit(f,x,0,'left')f=(x+a/x)^x;limit(f,x,inf)4syms x y mf=sqrt(x+sqrt(x+sqrt(x)));m=diff(f,'x')diff(m,'x')syms x y;f=x+y-sqrt(x^2+y^2);z1=diff(f,x)z2=diff(f,y)5syms x y;f=x+y-sqrt(x^2+y^2);z1=diff(f,x)z2=diff(f,y)sym x;f=1/(asin(x)^2*(1-x^2)^(1/2));int(f)6syms xf=1/(1+x);int(f,0,4)sym x;f=x^3*sin(x)^2/(x^6+2*x^4+1);int(f,-1,1)sym x;f=x^3*sin(x)^2/(x^6+2*x^4+1);int(f,-1,1)7syms ns=symsum(1/4^n,1,inf)sym n;s=symsum(((n+1)/n)^(1/2),1,inf)eval(y)8syms xf=tan(x);taylor(f,x,3,0)syms xf=sin(x)^2;taylor(f,x,5,0)9syms xx=solve('log(1+x)-5/(1+sin(x))=2','x')syms x y z[x y z]=solve('4*x^2/(4*x^2+1)=y','4*y^2/(4*y^2+1)=z','4*z^2/(4*z^2+1)=x','x','y','z') 10[x ,y]=dsolve('Dx=3*x+4*y','Dy=5*x-7*y','x(0)=0','y(0)=1','t')。
MATLAB程序设计与应用(第二版)课后实验答案
Matlab课后实验题答案实验一 MATLAB运算基础1. 先求下列表达式的值，然后显示MATLAB工作空间的使用情况并保存全部变量。
(1）0 122sin851ze =+(2）21ln(2z x=，其中2120.455ix+⎡⎤=⎢⎥-⎣⎦(3）0.30.330.3sin(0.3)ln, 3.0, 2.9,,2.9,3.0 22a ae e az a a--+=++=--（4)2242011122123t tz t tt t t⎧≤<⎪=-≤<⎨⎪-+≤<⎩，其中t=0:0.5：2.52. 已知：1234413134787,2033657327A B --⎡⎤⎡⎤⎢⎥⎢⎥==⎢⎥⎢⎥⎢⎥⎢⎥-⎣⎦⎣⎦求下列表达式的值:(1) A+6＊B 和A —B+I(其中I 为单位矩阵） （2） A*B 和A.＊B （3） A^3和A.^3 (4） A/B 及B\A（5） ［A,B ］和［A （[1,3］，:);B^2] 解：3. 设有矩阵A 和B123453166789101769,111213141502341617181920970212223242541311A B ⎡⎤⎡⎤⎢⎥⎢⎥-⎢⎥⎢⎥⎢⎥⎢⎥==-⎢⎥⎢⎥⎢⎥⎢⎥⎢⎥⎢⎥⎣⎦⎣⎦（1) 求它们的乘积C 。
(2） 将矩阵C 的右下角3×2子矩阵赋给D 。
(3) 查看MATLAB 工作空间的使用情况。
4. 完成下列操作：（1） 求[100，999]之间能被21整除的数的个数。
（2) 建立一个字符串向量，删除其中的大写字母。
解:(1） 结果:（2）.建立一个字符串向量 例如： ch='ABC123d4e56Fg9';则要求结果是：实验二 MATLAB 矩阵分析与处理1。
设有分块矩阵33322322E R A O S ⨯⨯⨯⨯⎡⎤=⎢⎥⎣⎦，其中E 、R 、O 、S 分别为单位矩阵、随机矩阵、零矩阵和对角阵，试通过数值计算验证22E R RS A OS +⎡⎤=⎢⎥⎣⎦。
MATLAB程序设计教程(第二版)课后答案3-8
MA TLAB 第二版课后答案unit2-8第二章1 求下列表达式的值。
（1）w=sqrt(2)*(1+0.34245*10^(-6)) (2) a=3.5; b=5; c=-9.8;x=(2*pi*a+(b+c)/(pi+a*b*c)-exp(2))/tan(b+c)+a (3)a=3.32; b=-7.9;y=2*pi*a^(2)*[(1-pi/4)*b-(0.8333-pi/4)*a](4)t=[2,1-3*i;5,-0.65];z=1/2*exp(2*t)*log(t+sqrt(1+t^(2)))2 求下列表达式A=[-1,5,-4;0,7,8;3,61,7]; B=[8,3,-1;2,5,3;-3,2,0]; (1)A+6*B A^2-B+eye (2)A*B A.*B B.*A (3)A/B B\A(4)[A,B] [A([1,3],:);B^2]3 根据已知，完成下列操作 （1）A=[23,10,-0.778,0;41,-45,65,5;32,5,0,32;6,-9.54,54,3.14]; K=find(A>10&A<25); A(K)（2）A=[23,10,-0.778,0;41,-45,65,5;32,5,0,32;6,-9.54,54,3.14]; B=A(1:3,:)C=A(:,1:2)D=A(2:4,3:4) E=B*C（3）E<D E&D E|D ~E|~Dunit3 实验指导1、 n=input('请输入一个三位数：'); a=fix(n/100);b=fix((n-a*100)/10); c=n-a*100-b*10; d=c*100+b*10+a 2（1）n=input('请输入成绩'); switch ncase num2cell(90:100) p='A';case num2cell(80:89) p='B';case num2cell(70:79) p='C';case num2cell(60:69) p='D'; otherwise p='E'; endprice=p（2）n=input('请输入成绩'); if n>=90&n<=100 p='A';elseif n>=80&n<=89 p='B';elseif n>=70&n<=79 p='C';elseif n>=60&n<=69 p='D'; elsep='E'; end price=p （3）try n; catchprice='erroe'end3n=[1,5,56,4,3,476,45,6,3,76,45,6,4,3,6,4,23,76 ,908,6];a=n(1)；b=n(1);for m=2:20if n(m)>aa=n(m);elseif n(m)<bb=n(m);endendmax=amin=b法2n=[1,5,56,4,3,476,45,6,3,76,45,6,4,3,6,4,23,76 ,908,6];min=min(n)max=max(n)4b=[-3.0:0.1:3.0];for n=1:61a=b(n);y(n)=(exp(0.3*a)-exp(-0.3*a))/2*sin(a+0.3)+l og((0.3+a)/2);endy5y1=0;y2=1;n=input('请输入n的值：');for i=1:ny1=y1+1/i^2;y2=y2*((4*i*i)/((2*i-1)*(2*i+1)));endy1y27（1）f=[];for n=1:40f(n)=n+10*log(n^2+5);endy=f(40)/(f(30)+f(20))（2）f=[];a=0;for n=1:40f(n)=a+n*(n+1);a=f(n);endy=f(40)/(f(30)+f(20))8y=0;m=input('输入m的值:');n=input('输入n值：');for i=1:ny=y+i^m;endy********************************* ***************************function s=shi8_1(n,m)s=0;for i=1:ns=s+i^m;end********************************* ***************************shi8_1(100,1)+shi8_1(50,2)+shi8_1(10,1 /2)unit4实验指导1（1）x=-10:0.05:10;y=x-x.^3./6;plot(x,y)（2）x=-10:0.5:10;ezplot('x^2+2*y^2-64',[-8,8]);grid on;2t=-pi:pi/10:pi;y=1./(1+exp(-t));subplot(2,2,1);bar(t,y);title('条形图(t,y)');axis([-pi,pi,0,1]);subplot(2,2,2);stairs(t,y,'b');title('阶梯图(t,y)');axis([-pi,pi,0,1]);subplot(2,2,3);stem(t,y,'k');title('杆图(t,y)');axis([-pi,pi,0,1]);subplot(2,2,4);loglog(t,y,'y');title('对数坐标图(t,y)');3（1）t=0:pi/50:2*pi;r=5.*cos(t)+4;polar(t,r);title('\rho=5*cos\theta+4'); （2）t=-pi/3:pi/50:pi/3;r=5.*((sin(t)).^2)./cos(t);polar(t,r);unit5实验指导1A=randn(10,5)x=mean(A)y=std(A)Max=max(max(A))Min=min(min(A))Sumhang=sum(A,2)SumA=sum(Sumhang)B=sort(A);C=sort(B,2,'descend');C2（1）a=0:15:90;b=a./180.*pi;s=sin(b)c=0:15:75;d=c./180.*pi;t=tan(d)e=input('请输入想计算的值：'); S=sin(e/180*pi)T=tan(e/180*pi)S1=interp1(a,s,e,'spline')T1=interp1(c,t,e,'spline')P1=polyfit(a,s,5);P2=polyfit(c,t,5); S2=polyval(P1,e)T2=polyval(P2,e)（2）n=[1,9,16,25,36,49,64,81,100];N=sqrt(n);x=input('ji suan zhi : ');interp1(n,N,x,'cubic')3N=64;T=5;t=linspace(0,T,N);h=exp(-t);dt=t(2)-t(1);f=1/dt;X=fft(t);F=X(1:N/2+1);f=f*(0:N/2)/N;plot(f,abs(F),'-*')4P=[2,-3,0,5,13];Q=[1,5,8];p=polyder(P)q=polyder(P,Q)[a,b]=polyder(P,Q)5P1=[1,2,4,0,5];P2=[0,1,2];P3=[1,2,3];P=P1+conv(P2,P3)X=roots(P)A=[-1,1.2,-1.4;0.75,2,3.5;0,5,2.5];p=polyval(P,A)unit6实验指导1A=[1/2,1/3,1/4;1/3,1/4,1/5;1/4,1/5,1/6]; p=[0.95,0.67,0.52]';x=A\pA=[1/2,1/3,1/4;1/3,1/4,1/5;1/4,1/5,1/6]; p=[0.95,0.67,0.53]';x=A\pcond(A)2（1）x1=fzero(@funx1,-1)function fx=funx1(x)fx=x^41+x^3+1;（2）x2=fzero(@funx2,0.5)function fx=funx2(x)fx=x-sin(x)/x;（3）options=optimset('Display','off'); x=fsolve(@fun3,[1,1,1]',options)q=fun3(x)function q=fun3(p)x=p(1);y=p(2);z=p(3);q(1)=sin(x)+y^2+log(z)-7;q(2)=3*x+2^y-z^3+1;q(3)=x+y+z-5;3（1）t0=0;tf=5;y0=1;[t,y]=ode23(@fun4,[t0,tf],y0); t'y'function yp=fun4(t,y)yp=-(1.2+sin(10*t))*y;（2）t0=0;tf=5;y0=1;[t,y]=ode23(@fun5,[t0,tf],y0); t'y'function yp=fun5(t,y)yp=cos(t)-y/(1+t^2);4x=fminbnd(@mymin,0,2);-mymin(x)function fx=mymin(x)fx=-(1+x.^2)/(1+x.^4);5options=optimset('Display','off');[x,fval]=fmincon(@fun6,[0,0,0],[],[],a,b,l b,ub)-fvalfunction f=fun6(x)f=-(sqrt(x(1))+(400-x(1))*1.1+(sqrt(x(2)) +(400-x(1))*1.1-x(2))*1.1+sqrt(3)+(((400-x(1 ))*1.1-x(2))*1.1-x(3))*1.1+sqrt(x(x4)));unit7实验指导1（1）format longfx=inline('sin(x)./x');[I,n]=quadl(fx,0,2,1e-10)（2）format longfx=inline('1./((x-0.3).^2+0.01)-1./((x-0.9) .^2+0.04)-6');[I,n]=quad(fx,0,1,1e-10)2（1）global ki;ki=0;I=dblquad(@fxy,0,1,0,1)ki（2）f=inline('abs(cos(x+y))','x','y');I=dblquad(f,0,pi,0,pi)3X=0.3:0.2:1.5;F=[0.3895,0.6598,0.9147,1.1611,1.3971, 1.6212,1.8325];trapz(X,F)4p=0:pi/5:2*pi;for n=1:3nDX=diff(sin(p),n)end5f=inline('sin(x)./(x+cos(2.*x))');g=inline('(cos(x).*(x+cos(2*x))-sin(x).*( 1-2.*sin(2*x)))/(x+cos(2.*x)).^2');x=-pi:0.01:pi;p=polyfit(x,f(x),5);dp=polyder(p);dpx=polyval(dp,x); %求dp在假设点的函数值dx=diff(f([x,3.01]))/0.01; %直接对f(x)求数值导数gx=g(x);%求函数f的导函数g在假设点的导数plot(x,dpx,x,dx,'.',x,gx,'-'); %作图unit8实验指导1syms x y;s=x^4-y^4;factor(s)factor(5135)2syms x;f=(x-2)/(x^2-4);limit(f,x,2)sym x;f=(sqrt(pi)-sqrt(acos(x)))/sqrt(x+1);limit(f,x,-1,'right')3sym x;f=sin(1/x);diff(f,'x')diff(f,'x',2sym x;f=(1-cos(2*x))/x;diff(f,'x')diff(f,'x',2)4sym x;f=sqrt(exp(x)+1);int(f,'x')syms x y;f=x/(x+y);int(f,'y')sym x;f=exp(x)*(1+exp(x))^2;int(f,'x',0,log(2))sym x;f=x*log(x);int(f,'x',1,exp(1))5sym x;s=symsum((-1)^(x+1)/x,1,Inf)sym y;z=symsum(y^(2*y-1)/(2*y-1),1,Inf)6sym x;f1=(exp(x)+exp(-x))/2;f2=sqrt(x^3-2*x+1);taylor(f1,x,5,0)taylor(f2,x,6,0)7syms x y a;x=solve('x^3+a*x+1=0','x')x=solve('sin(x)+2*cos(x)-sqrt(x)=0','x')[xy]=solve('log(x/y)=9','exp(x+y)=3','x','y') 8syms n;[x,y]=dsolve('x*(D2y)+(1-n)*(Dy)+y=0',' y(0)=0','Dy(0)=0','x')。
matlab程序设计(第二版)课后作业答案
一、实验结果：1、利用函数eye，ones，zeros，rand，randn 函数分别产生首先编写脚本函数如下:a1=eye(3)a2=eye(15,8)b1=ones(3)b2=ones(15,8)c1=zeros(3)c2=zeros(15,8)d1=2*rand(3,3)-1d2=2*randn(3,3)+1r1=2*rand(15,8)-1r2=2*randn(15,8)+12、使用函数diag和reshape函数：编写脚本：a1=[8 -7 2];a2=diag(a1);a3=fliplr(a2);a4=[5 3];a5=diag(a4,-1);a6=fliplr(a5);a=a3+a6a1=reshape(a,1,9)b1=[4 5 7];b2=diag(b1);b3=fliplr(b2);b4=[2 0 8];b5=diag(b4);b=b3+b5b6=reshape(b,1,9)3、直接在工作空间里输入：a=5-round(100*rand(50,2))/104、脚本文件：a=[-pi:2*pi/360:pi];y1=sin(a)y2=cos(a)5.、编写脚本：A=rand(10)b=A>0.6[i,j,v]=find(b)c=sum(v)6、编写脚本：A=randn(10)b=-0.5<A<0.5[i,j,v]=find(b);c=sum(v)7、编写实现表中功能的语句：if and(a<1,b<=0.5)语句1elseif and(a<1,b>0.5)语句2elseif and(a>=1,b<=0.5)语句3elseif and(a>=1,b>0.5)语句4elsedisp('error')end8、编写脚本如下：A=2*rand(3)b=A>1c=A.*b;[i,j,v]=find(c);v9、编写脚本函数：A=101*rand(100,3)b=A>100;c=A.*b;[i,j,d]=find(c);d10、为节约空间，用5*5的矩阵来模拟100*100的矩阵：编写脚本函数如下：A=[0 2 0 3 0;0 0 0 0 0;0 8 0 5 0;0 4 0 5 0;0 4 0 2 0]b=any(A);[i,j,v]=find(1-b);A(:,j)=[];B=A';c=any(B);[i,j,v]=find(1-c);B(:,j)=[];A=B'一、实验结果：1、输入脚本函数：x=0:pi/50:2*pi;k=[1 26 51 76 101];x(k)=[];figure(1)subplot(2,2,1)plot(x,sin(x)),grid onsubplot(2,2,2)plot(x,cos(x)),grid onsubplot(2,2,3)plot(x,tan(x)),grid onsubplot(2,2,4)plot(x,cot(x)),grid on2、分别利用title函数给图形加上标题，用text函数给坐标系中的建立文本对象，可将字符串放在图形的指定位置，用xlabel、ylabel函数添加x、y轴的标记，用legend 函数给图形加上插图说明。
(完整word版)MATLAB程序设计及应用(第二版)课后实验答案
Matlab 课后实验题答案实验一 MATLAB 运算基础1。
先求下列表达式的值，然后显示MATLAB 工作空间的使用情况并保存全部变量。
(1） 0122sin851z e =+ (2）21ln(2z x =，其中2120.455i x +⎡⎤=⎢⎥-⎣⎦ (3） 0.30.330.3sin(0.3)ln , 3.0, 2.9,,2.9,3.022a a e e az a a --+=++=--(4） 2242011122123t t z t t t t t ⎧≤<⎪=-≤<⎨⎪-+≤<⎩，其中t =0:0。
5:2。
52。
已知：1234413134787,2033657327A B --⎡⎤⎡⎤⎢⎥⎢⎥==⎢⎥⎢⎥⎢⎥⎢⎥-⎣⎦⎣⎦求下列表达式的值：（1） A+6*B 和A —B+I （其中I 为单位矩阵） (2) A*B 和A 。
*B (3） A^3和A.^3 (4） A/B 及B\A（5） ［A,B ］和［A （［1，3］,：）;B^2］3。
设有矩阵A 和B1234530166789101769,111213141502341617181920970212223242541311A B ⎡⎤⎡⎤⎢⎥⎢⎥-⎢⎥⎢⎥⎢⎥⎢⎥==-⎢⎥⎢⎥⎢⎥⎢⎥⎢⎥⎢⎥⎣⎦⎣⎦(1） 求它们的乘积C.(2） 将矩阵C 的右下角3×2子矩阵赋给D 。
（3) 查看MATLAB 工作空间的使用情况。
4. 完成下列操作：（1） 求［100,999］之间能被21整除的数的个数。
（2) 建立一个字符串向量，删除其中的大写字母。
(2). 建立一个字符串向量 例如:ch=’ABC123d4e56Fg9'；则要求结果是：实验二 MATLAB 矩阵分析与处理1. 设有分块矩阵33322322E R A O S ⨯⨯⨯⨯⎡⎤=⎢⎥⎣⎦，其中E 、R 、O 、S 分别为单位矩阵、随机矩阵、零矩阵和对角阵，试通过数值计算验证22E R RS A O S +⎡⎤=⎢⎥⎣⎦。
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MATLAB 第二版课后答案unit3-8 unit3实验指导1、 n=input('请输入一个三位数：');a=fix(n/100);b=fix((n-a*100)/10);c=n-a*100-b*10;d=c*100+b*10+a2（1）n=input('请输入成绩');switch ncase num2cell(90:100)p='A';case num2cell(80:89)p='B';case num2cell(70:79)p='C';case num2cell(60:69)p='D';otherwisep='E';endprice=p（2）n=input('请输入成绩');if n>=90&n<=100p='A';elseif n>=80&n<=89p='B';elseif n>=70&n<=79p='C';elseif n>=60&n<=69p='D';elsep='E';endprice=p（3）tryn;catchprice='erroe'end3n=[1,5,56,4,3,476,45,6,3,76,45,6,4,3,6,4,23,76,908,6];b=n(1);for m=2:20if n(m)>aa=n(m);elseif n(m)<bb=n(m);endendmax=amin=b法2n=[1,5,56,4,3,476,45,6,3,76,45,6,4,3,6,4,23,76,908,6];min=min(n)max=max(n)4b=[-3.0:0.1:3.0];for n=1:61a=b(n);y(n)=(exp(0.3*a)-exp(-0.3*a))/2*sin(a+0.3)+log((0.3+a)/2);endy5y1=0;y2=1;n=input('请输入n 的值：');for i=1:ny1=y1+1/i^2;y2=y2*((4*i*i)/((2*i-1)*(2*i+1)));endy1y26A=[1,1,1,1,1,1;2,2,2,2,2,2;3,3,3,3,3,3;4,4,4,4,4,4;5,5,5,5,5,5;6,6,6,6,6,6]; n=input('请输入n 的值:');if n<=5&n>=0disp(A([n],:));elseif n<0disp(lasterr);else disp(A([6],:));disp(lasterr);end7（1）f=[];f(n)=n+10*log(n^2+5);endy=f(40)/(f(30)+f(20))（2）f=[];a=0;for n=1:40f(n)=a+n*(n+1);a=f(n);endy=f(40)/(f(30)+f(20))8y=0;m=input('输入m 的值:');n=input('输入n 值：');for i=1:ny=y+i^m;endy************************************************************ function s=shi8_1(n,m)s=0;for i=1:ns=s+i^m;end************************************************************ shi8_1(100,1)+shi8_1(50,2)+shi8_1(10,1/2)思考练习2N=[1,2,3,4,5];2.*NN./21./N1./N.^23s=fix(100*rand(1,20)*9/10+10)y=sum(s)/20j=0;for i=1:20if s(i)<y&rem(s(i),2)==0j=j+1;A(j)=s(i);else continue;endendA4y1=0;y2=0;n=input('请输入n 的值：'); for i=1:ny1=y1+-(-1)^i/(2*i-1);y2=y2+1/4^i;endy1y2unit4实验指导1（1）x=-10:0.05:10;y=x-x.^3./6;plot(x,y)（2）x=-10:0.5:10;ezplot('x^2+2*y^2-64',[-8,8]); grid on;2t=-pi:pi/10:pi;y=1./(1+exp(-t));subplot(2,2,1);bar(t,y);title('条形图(t,y)');axis([-pi,pi,0,1]);subplot(2,2,2);stairs(t,y,'b');title('阶梯图(t,y)');axis([-pi,pi,0,1]);subplot(2,2,3);stem(t,y,'k');title('杆图(t,y)');axis([-pi,pi,0,1]);subplot(2,2,4);loglog(t,y,'y');title('对数坐标图(t,y)');3（1）t=0:pi/50:2*pi;r=5.*cos(t)+4;polar(t,r);title('\rho=5*cos\theta+4'); （2）t=-pi/3:pi/50:pi/3;r=5.*((sin(t)).^2)./cos(t); polar(t,r);4（1）t=0:pi/50:2*pi;x=exp(-t./20).*cos(t);y=exp(-t./20).*sin(t);z=t;plot3(x,y,z);grid on;（2）[x,y]=meshgrid(-5:5);z=zeros(11)+5;mesh(x,y,z);shading interp;5[x,y,z]=sphere(20);surf(x,y,z);axis off;shading interp;m=moviein(20);for i=1:20axis([-i,i,-i,i,-i,i])m(:,i)=getframe;endmovie(m,4);思考练习2（1）x=-5:0.1:5;y=(1./(2*pi)).*exp((-(x.^2))/2); plot(x,y);（2）t=-2*pi:0.1:2*pi;x=t.*sin(t);y=t.*cos(t);plot(x,y);grid on;3t=0:pi/1000:pi;x=sin(3.*t).*cos(t);y1=sin(3.*t).*sin(t);y2=2.*x-0.5;plot(x,y1,'k',x,y2);hold on;k=find(abs(y1-y2)<1e-2);x1=x(k);y3=2.*x1-0.5;plot(x1,y3,'rp');4x=-2:0.01:2;y=sin(1./x);subplot(2,1,1);plot(x,y);subplot(2,1,2);fplot('sin(1./x)',[-2,2],1e-4);5（1）i=-4*pi:0.1:10;j=12./sqrt(i);polar(i,j);title('{\rho}=12/sqrt(\theta)')（2）a=-pi/6:0.01:pi/6;b=3.*asin(a).*cos(a)./((sin(a)).^3+(cos(a)).^3); polar(a,b);6（1）[u,v]=meshgrid(-4:0.1:4);x=3.*u.*sin(v);y=2.*u.*cos(v);z=4.*u.^2;subplot(2,1,1);mesh(x,y,z);subplot(2,1,2);surf(x,y,z);（2）[x,y]=meshgrid(-3:0.2:3);z=-5./(1+x.^2+y.^2);subplot(1,2,1);mesh(x,y,z);subplot(1,2,2);surf(x,y,z);unit5实验指导1A=randn(10,5)x=mean(A)y=std(A)Max=max(max(A))Min=min(min(A))Sumhang=sum(A,2)SumA=sum(Sumhang)B=sort(A);C=sort(B,2,'descend');C2（1）a=0:15:90;b=a./180.*pi;s=sin(b)c=0:15:75;d=c./180.*pi;t=tan(d)e=input('请输入想计算的值：'); S=sin(e/180*pi)T=tan(e/180*pi)S1=interp1(a,s,e,'spline')T1=interp1(c,t,e,'spline')P1=polyfit(a,s,5);P2=polyfit(c,t,5);S2=polyval(P1,e)T2=polyval(P2,e)（2）n=[1,9,16,25,36,49,64,81,100]; N=sqrt(n);x=input('ji suan zhi : ');interp1(n,N,x,'cubic')3N=64;T=5;t=linspace(0,T,N);h=exp(-t);dt=t(2)-t(1);f=1/dt;X=fft(t);F=X(1:N/2+1);f=f*(0:N/2)/N;plot(f,abs(F),'-*')4P=[2,-3,0,5,13];Q=[1,5,8];p=polyder(P)q=polyder(P,Q)[a,b]=polyder(P,Q)5P1=[1,2,4,0,5];P2=[0,1,2];P3=[1,2,3];P=P1+conv(P2,P3)X=roots(P)A=[-1,1.2,-1.4;0.75,2,3.5;0,5,2.5];p=polyval(P,A)思考练习4A=rand(1,30000);a=mean(A)b=std(A)Max=max(A)Min=min(A)n=0;for i=1:30000if(A(i)>0.5)n=n+1;endendny=n/300005p=[45,74,54,55,14;78,98,45,74,12;87,98,85,52,65][M,S]=max(p)[N,H]=min(p)junzhi=mean(p,1)fangcha=std(p,1,1)zong=sum(p,2);[Max,wei]=max(zong)[Min,wei]=min(zong)[zcj,xsxh]=sort(zong,'descend')6x=[1:10:101];y=[0,1.0414,1.3222,1.4914,1.6128,1.7076,1.7853,1.8513,1.9085,1.9590,2.0043]; [p,s]=polyfit(x,y,5)a=1:5:101;y1=polyval(p,a);plot(x,y,':o',a,y1,'-*')unit6实验指导1A=[1/2,1/3,1/4;1/3,1/4,1/5;1/4,1/5,1/6];p=[0.95,0.67,0.52]';x=A\pA=[1/2,1/3,1/4;1/3,1/4,1/5;1/4,1/5,1/6]; p=[0.95,0.67,0.53]';x=A\pcond(A)2（1）x1=fzero(@funx1,-1)function fx=funx1(x)fx=x^41+x^3+1;（2）x2=fzero(@funx2,0.5)function fx=funx2(x)fx=x-sin(x)/x;（3）options=optimset('Display','off');x=fsolve(@fun3,[1,1,1]',options)q=fun3(x)function q=fun3(p)x=p(1);y=p(2);z=p(3);q(1)=sin(x)+y^2+log(z)-7;q(2)=3*x+2^y-z^3+1;q(3)=x+y+z-5;3（1）t0=0;tf=5;y0=1;[t,y]=ode23(@fun4,[t0,tf],y0);t'y'function yp=fun4(t,y)yp=-(1.2+sin(10*t))*y;（2）t0=0;tf=5;y0=1;[t,y]=ode23(@fun5,[t0,tf],y0);t'y'function yp=fun5(t,y)yp=cos(t)-y/(1+t^2);4x=fminbnd(@mymin,0,2);-mymin(x)function fx=mymin(x)fx=-(1+x.^2)/(1+x.^4);5options=optimset('Display','off');[x,fval]=fmincon(@fun6,[0,0,0],[],[],a,b,lb,ub)-fvalfunction f=fun6(x)f=-(sqrt(x(1))+(400-x(1))*1.1+(sqrt(x(2))+(400-x(1))*1.1-x(2))*1.1+sqrt(3)+(((400- x(1))*1.1-x(2))*1.1-x(3))*1.1+sqrt(x(x4)));思考练习1（1）A=[2,3,5;3,7,4;1,-7,1];B=[10,3,5]';C1=inv(A)*BC2=A\B[L,U]=lu(A);x=U\(L\B)（2）A=[6,5,-2,5;9,-1,4,-1;3,4,2,-2;3,-9,0,2];B=[-4,13,1,11]';C1=inv(A)*BC2=A\B[L,U]=lu(A);x=U\(L\B)2（1）x1=fzero(@funx1,1.5)function fx=funx1(x)fx=3*x+sin(x)-exp(x);（2）x1=fzero(@funx2,1)function fx=funx2(x)fx=x-1/x+5;（3）options=optimset('Display','off');x=fsolve(@fun3,[3,0]',options)q=fun3(x)function q=fun3(p)x=p(1);y=p(2);q(1)=x^2+y^2-9;q(2)=x+y-1;3（1）t0=0;tf=5;y0=[0,1];[t,y]=ode45(@vdpol,[t0,tf],y0);[t,y]function ydot=vdpol(t,y);ydot(1)=(2-3*y(2)-2*t*y(1))./(1+t^2);ydot(2)=y(1);ydot=ydot';（2）t0=0;tf=5;y0=[1;0;2];[t,y]=ode45(@vdpoll,[t0,tf],y0);[t,y]function ydot=vdpoll(t,y);ydot(1)=cos(t)-y(3)./(3+sin(t))+5*y(1).*cos(2*t)/((t+1).^2)-y(2); ydot(2)=y(1);ydot(3)=y(2);ydot=ydot';4x=fminbnd(@mymin,0,pi);-mymin(x)function fx=mymin(x)fx=-sin(x)-cos(x.^2);5[x,y1]=fminbnd(@mymax,0,1.5);-y1function fx=mymax(x);fx=-(9*x+4*x.^3-12*x.^2);unit7实验指导1（1）format longfx=inline('sin(x)./x');[I,n]=quadl(fx,0,2,1e-10)（2）format longfx=inline('1./((x-0.3).^2+0.01)-1./((x-0.9).^2+0.04)-6');[I,n]=quad(fx,0,1,1e-10)2（1）global ki;ki=0;I=dblquad(@fxy,0,1,0,1)ki（2）f=inline('abs(cos(x+y))','x','y');I=dblquad(f,0,pi,0,pi)3X=0.3:0.2:1.5;F=[0.3895,0.6598,0.9147,1.1611,1.3971,1.6212,1.8325];trapz(X,F)4p=0:pi/5:2*pi;for n=1:3nDX=diff(sin(p),n)end5f=inline('sin(x)./(x+cos(2.*x))');g=inline('(cos(x).*(x+cos(2*x))-sin(x).*(1-2.*sin(2*x)))/(x+cos(2.*x)).^2');x=-pi:0.01:pi;p=polyfit(x,f(x),5);dp=polyder(p);dpx=polyval(dp,x); %求dp 在假设点的函数值dx=diff(f([x,3.01]))/0.01; %直接对f(x)求数值导数gx=g(x); %求函数f 的导函数g 在假设点的导数plot(x,dpx,x,dx,'.',x,gx,'-'); %作图思考练习2format longfx=inline('1./(1+x.^2)');[I,n]=quad(fx,-Inf,Inf,1e-10)[I,n]=quadl(fx,-Inf,Inf,1e-10)x=-100000:100000;y=1./(1+x.^2);trapz(x,y)format short3(1)format longfx=inline('log(1+x)./(1+x.^2)');[I,n]=quad(fx,0,1,1e-10)(2)format longfx=inline('sqrt(cos(t.^2)+4*sin((2*t).^2)+1)'); [I,n]=quad(fx,0,2*pi,1e-10)4f=inline('4.*x.*z.*exp(-z.^2.*y-x.^2)');I=triplequad(f,0,pi,0,pi,0,1)5f=inline('sin(x)');g=inline('cos(x)');x=0:0.01:2*pi;p=polyfit(x,f(x),5);dp=polyder(p);dpx=polyval(dp,x);dx=diff(f([x,2*pi+0.01]))/0.01;gx=g(x);plot(x,dpx,x,dx,'.',x,gx,'-')unit8实验指导1syms x y;s=x^4-y^4;factor(s)factor(5135)2syms x;f=(x-2)/(x^2-4);limit(f,x,2)sym x;f=(sqrt(pi)-sqrt(acos(x)))/sqrt(x+1);limit(f,x,-1,'right')3sym x;f=sin(1/x);diff(f,'x')diff(f,'x',2)sym x;f=(1-cos(2*x))/x;diff(f,'x')diff(f,'x',2)4sym x;f=sqrt(exp(x)+1);int(f,'x')syms x y;f=x/(x+y);int(f,'y')sym x;f=exp(x)*(1+exp(x))^2;int(f,'x',0,log(2))sym x;f=x*log(x);int(f,'x',1,exp(1))5sym x;s=symsum((-1)^(x+1)/x,1,Inf)sym y;z=symsum(y^(2*y-1)/(2*y-1),1,Inf)6sym x;f1=(exp(x)+exp(-x))/2;f2=sqrt(x^3-2*x+1);taylor(f1,x,5,0)taylor(f2,x,6,0)7syms x y a;x=solve('x^3+a*x+1=0','x')x=solve('sin(x)+2*cos(x)-sqrt(x)=0','x')[x y]=solve('log(x/y)=9','exp(x+y)=3','x','y')8syms n;[x,y]=dsolve('x*(D2y)+(1-n)*(Dy)+y=0','y(0)=0','Dy(0)=0','x') 思考练习2syms x B1 B2 a bs1=2*((cos(x))^2)-(sin(x))^2;s2=sin(B1)*cos(B2)-cos(B1)*sin(B2);s3=sqrt((a+sqrt(a^2-b))/2)+sqrt((a-sqrt(a^2-b))/2); s4=(4*x^2+8*x+3)/(2*x+1);h1=simplify(s1)h2=simplify(s2)h3=simplify(s3)h4=simplify(s4)3syms x a;f=abs(x)/x;limit(f,x,0,'left')f=(x+a/x)^x;limit(f,x,inf)4syms x y mf=sqrt(x+sqrt(x+sqrt(x)));m=diff(f,'x')diff(m,'x')syms x y;f=x+y-sqrt(x^2+y^2);z1=diff(f,x)z2=diff(f,y)5syms x y;f=x+y-sqrt(x^2+y^2);z1=diff(f,x)z2=diff(f,y)sym x;f=1/(asin(x)^2*(1-x^2)^(1/2));int(f)6syms xf=1/(1+x);int(f,0,4)sym x;f=x^3*sin(x)^2/(x^6+2*x^4+1);int(f,-1,1)sym x;f=x^3*sin(x)^2/(x^6+2*x^4+1);int(f,-1,1)7syms ns=symsum(1/4^n,1,inf)sym n;s=symsum(((n+1)/n)^(1/2),1,inf)eval(y)8syms xf=tan(x);taylor(f,x,3,0)syms xf=sin(x)^2;taylor(f,x,5,0)9syms xx=solve('log(1+x)-5/(1+sin(x))=2','x')syms x y z[x y z]=solve('4*x^2/(4*x^2+1)=y','4*y^2/(4*y^2+1)=z','4*z^2/(4*z^2+1)=x','x','y','z') 10[x ,y]=dsolve('Dx=3*x+4*y','Dy=5*x-7*y','x(0)=0','y(0)=1','t')。