MATLAB程序设计教程(第二版)课后答案(最新整理)

1、matlab 第二版课后答案 unit3-8unit3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;end price=p（2） n=input(请输入成绩); if n=90&n=

2、80&n=70&n=60&naa=n(m); elseif n(m)bb=n(m);endendmax=a min=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); endy 5y1=0; y2=1;n=input(请输入 n 的值：); for i=1:ny1=y1+1/i2; y2=y2*(4*i*i)/(

3、2*i-1)*(2*i+1);end y1 y2 6a=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=0disp(a(n,:); elseif n0disp(lasterr); else disp(a(6,:);disp(lasterr);end7（1） f=;for n=1:40f(n)=n+10*log(n2+5);endy=f(40)/(f(30)+f(20)（2）f=;a=0;for n=1:40f(n)=a+n*(n+1); a=f(n)

4、;end y=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+im;end y* function s=shi8_1(n,m)s=0;for i=1:ns=s+im;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./2 1./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)=0 j=j+1;

5、a(j)=s(i); else continue; endend a 4y1=0;y2=0;n=input(请输入 n 的值：); for i=1:ny1=y1+-(-1)i/(2*i-1); y2=y2+1/4i;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(x2+2*y2-64,-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,

6、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*costheta+4);（2）t=-pi/3:pi/50:pi/3; r=5.*(sin(t).2)./cos(t); polar(t,r)

7、;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;5x,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;end movie(m,4); 思考练习2（1

8、）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)0.5)n=n+1;endend ny=n/30000 5p=45,74,54,55,14;78,98,45,74,12;87,98,85

9、,52,65m,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,-*) unit

10、6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=ap a=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=ap cond(a) 2（1）x1=fzero(funx1,-1)function fx=funx1(x) fx=x41+x3+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,

11、1,options)q=fun3(x)function q=fun3(p) x=p(1);y=p(2);z=p(3);q(1)=sin(x)+y2+log(z)-7; q(2)=3*x+2y-z3+1; q(3)=x+y+z-5;3（1） t0=0;tf=5; y0=1;t,y=ode23(fun4,t0,tf,y0); tyfunction 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); tyfunction yp=fun5(t,y)yp=cos(t)-y/(1+t2); 4x=fm

12、inbnd(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

13、,1; b=10,3,5;c1=inv(a)*b c2=ab l,u=lu(a);x=u(lb)（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)*b c2=ab l,u=lu(a);x=u(lb) 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

14、(fun3,3,0,options)q=fun3(x)function q=fun3(p) x=p(1);y=p(2);q(1)=x2+y2-9; q(2)=x+y-1;3（1） t0=0;tf=5; y0=0,1;t,y=ode45(vdpol,t0,tf,y0); t,yfunction ydot=vdpol(t,y);ydot(1)=(2-3*y(2)-2*t*y(1)./(1+t2); ydot(2)=y(1);ydot=ydot;（2）t0=0;tf=5; y0=1;0;2;t,y=ode45(vdpoll,t0,tf,y0); t,yfunction ydot=vdpoll(t,y

15、);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); 5x,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,

16、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

17、; for n=1:3n dx=diff(sin(p),n)end 5f=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

18、,gx,-);%作图思考练习2format long fx=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 short 3(1)format long fx=inline(log(1+x)./(1+x.2);i,n=quad(fx,0,1,1e-10)(2)format long fx=inline(sqrt(cos(t.2)+4*sin(2*t).2)+1); i,n=quad(fx,0,2*pi

19、,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=x4-y4; factor(s)factor(5135) 2syms x;f=

20、(x-2)/(x2-4); 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

21、,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(x3-2*x+1); taylor(f1,x,5,0)taylor(f2,x,6,0) 7syms x y a; x=solve(x3+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)+

22、(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(a2-b)/2)+sqrt(a-sqrt(a2-b)/2); s4=(4*x2+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;

23、limit(f,x,inf) 4syms x y m f=sqrt(x+sqrt(x+sqrt(x); m=diff(f,x)diff(m,x)syms x y;f=x+y-sqrt(x2+y2); z1=diff(f,x) z2=diff(f,y)5syms x y;f=x+y-sqrt(x2+y2); z1=diff(f,x) z2=diff(f,y)sym x;f=1/(asin(x)2*(1-x2)(1/2); int(f)6syms x f=1/(1+x); int(f,0,4)sym x; f=x3*sin(x)2/(x6+2*x4+1); int(f,-1,1)sym x; f=x3*sin(x)2/(x6+2*x4+1); int(f,-1,1)7syms n s=symsum(1/4n,1,inf)sym n; s=symsum(n+1)/n)(1/2),1,inf) eval(y)8syms x f=tan(x); taylor(f,x,3,0)syms x f=sin(x)2; taylor(f,x,5,0)9syms xx=solve(log(1+x)-5/(1+sin(x)=2,x)syms x y zx y z=solve(4*x2/(4*x2+1)=y,4*y2