精讲多练MATLAB(第二版)课后习题答案

第1章练习题答案1-2.A=1.2 ;B=-4.6 ;C=8.0 ;D=3.5 ;E=-4.0;T=atan(2*pi*A+E/(2*pi*B*C)/D)1-3clearx=45;(sin(x*pi/180)+sqrt(35)/(72(1/5)1-4cleara=5.67;b=7.811;exp(a+b)/log10(a+b)1-5clearx=3;y=sqrt(x)-6*(x+1/x)+(x-3.2)2/(x+7.7)31-6clearr=15;d=2*rc=2*pi*rs=pi*r*r1-7cleara=8.5;b=14.6;c=18.4;s=(a+b+c)/2;area=sqrt(s*(s-a)*(s-b)*(s-c)第2章练习题答案2-1 clearA= 3 1 1;2 1 2;1 2 3;B=1 1 -1;2 -1 0;1 -1 1;2*A+B,4*(A2)-3*(B2),A*B,B*A,A*B-B*A2-2 clearA=1/3 0 0;0 1/4 0;0 0 1/7;B=inv(inv(A)-eye(3)*62-3 clearB=1 2 -3 -2;0 1 2 -3;0 0 1 2;0 0 0 1;C=1 2 0 1;0 1 2 0;0 0 1 2;0 0 0 1;A=(inv(2*eye(4)-inv(C)*B)*inv(C)2-4 clearA=2 -1;-1 2;B=0 -2;-2 0;X=(1/2)*(B+2*A)2-5 clearA=2 -3 0 2;1 5 2 1;3 -1 1 -1;4 1 2 2;B=8;2;7;12;X=AB2-6 A=3 12 4 7 0 8 1;p=poly2str(A,x)x=roots(A)2-7 A=3 12 4 7 0 8 1;B=1 -3 5 -15 0;div,rest=deconv(A,B)第三章3-1.x=sym(x);limit(cos(sqrt(x)(pi/x),x,0,right) ans =exp(-1/2*pi)3-2.x=sym(x);f=sym(3*sin(x)+x2*cos(1/x)/(1+cos(x)*log(1+x);limit(f,x,0)ans =3/23-3.x=sym(x);f=sym(sqrt(4*x2+x-1)+x+1)/sqrt(x2+sin(x);limit(f,x,-inf)ans =13-4.syms x y;f=sym(x2+y2)(x2*y2);limit(limit(f,x,0),y,0)ans =13-5.x=sym(x);y=sym(tan(sqrt(x+sqrt(x+sqrt(2*x)2);diff(y,x)ans =tan(x+(x+2(1/2)*x(1/2)(1/2)(1/2)*(1+tan(x+(x+2(1/2)*x(1/2)(1/2)(1/2)2)/(x+(x+2(1/2)*x(1/2)(1/2)(1/2)*(1+1/2/(x+2(1/2)*x(1/2)(1/2)*(1+1/2*2(1/2)/x(1/2) 3-6.x=sym(x);y=sym(cos(x2)*sin(1/x)2);diff(y,x)ans =-2*sin(x2)*x*sin(1/x)2-2*cos(x2)*sin(1/x)*cos(1/x)/x23-7.x=sym(x);y=sym(sqrt(sin(x)-sin(x)3);int(y,x,0,pi) ans =4/33-8.x=sym(x);y=sym(sqrt(x+1)/(x-1)/x);int(y,x) ans =-(1+x)/(x-1)(1/2)*(x-1)*(atan(1/(-1+x2)(1/2)-log(x+(-1+x2)(1/2)/(1+x)*(x-1)(1/2)3-9.dsolve(D2y+4*Dy+4*y=exp(-2*x),x) ans = 1/2*exp(-2*x)*(2*C2+2*x*C1+x2)3-10.dsolve(x2*Dy+x*y=y2,y(1)=1) ans =x*exp(1/x)/(exp(1/x)+exp(1/x*t)*x-exp(1/x*t)第四章4-1.plot(1 2 4 0 5 10 11 21 3 1)4-2.t=0:pi/100:2*pi;x=cos(t);y=sin(t);plot(x,y);axis(square);4-3.R=1 5 10 20;I=0:0.1:10;U=I*R;plot(I,U);4-4.mon=1:12;temp=0.2 2.3 8.7 18.5 24.6 32.1 36.8 37.1 28.3 17.8 6.4 -3.2;rainf=4.6 3.6 2.1 2.9 3.0 2.7 2.2 2.5 4.3 3.4 2.1 3.7;plot(mon,temp,r-p,mon,rainf,b:s);xlabel(month);ylabel(temperature and rainfall);%title(Temperature and Rainfall Curve);%text(3,1,rainfall);%text(9,28.3,temperature); flag=12;while(flag) text(mon(flag),temp(flag),num2str(mon(flag),num2str(temp(flag); text(mon(flag),rainf(flag),num2str(mon(flag),num2str(rainf(flag); flag=flag-1;end4-5.A=1 1 1 1 1 1 1;1 2 2 2 2 2 1;1 2 2 3 2 2 1;1 2 2 2 2 2 1;1 1 1 1 1 1 1;plot(A);4-6.x=-10:0.5:10;y=x;X,Y=meshgrid(x,y);Z=X.2+Y.2;surf(X,Y,Z);4-7.clccleartheta=(0:0.1:2)*pi;phi=(0:0.1:2)*pi;x=zeros(length(theta),length(phi);y=x;z=x;for i=1:length(theta) for j=1:length(phi) x(i,j)=2*sin(theta(i)*cos(phi(j); y(i,j)=3*sin(theta(i)*sin(phi(j); end z(i,:)=4*cos(theta(i);endaxis square subplot(2,2,1);mesh(x,y,z)title(三维)subplot(2,2,2);mesh(x,y,z)view(90,0)title(X轴视图)subplot(2,2,3);mesh(x,y,z)view(0,0)title(Y轴视图)subplot(2,2,4);mesh(x,y,z)view(0,90)title(Z轴视图)第五章5-1：clear;x=-2:0.01:2;for ii=1:401 if(x(ii)0) y(ii)=x(ii)+1; elseif (x(ii)=0) y(ii)=1; elseif(x(ii)=1) y(ii)=x(ii)3; endendplot(x,y);5-2：function y=fenduan(x)if(x0) y=x+1;elseif (x=0) y=1;elseif(x=1) y=x3;end5-3：建立文件arcsin.m如下：function y=arcsin(x)if abs(x)1 disp(输入参数的绝对值必须小于1); return;endn=0;y=0;u=x;while ueps u=(jiecheng(2*n)*x(2*n+1)/(2(2*n)*(jiecheng(n)2*(2*n+1); y=y+u; n=n+1;end建立文件jiecheng.m如下：function y=jiecheng(n)if(na,b=shuliang(36,100)5-5：for i=2:999 ge=rem(i,10); shi=rem(fix(i/10),10); bai=fix(i/100); if rem(ge+shi+bai),2) & isprime(i) disp(i); endend5-6：function y=issushu(n)y=1;for ii=2:fix(n/2) if(rem(n,ii)=0) y=0; endend习题1（程序段后面的是其运行的结果）例题1.2functionlt12a=1+2*i;b=3-4*i;disp(a+b=,num2str(a+b)disp(a-b=,num2str(a-b)disp(a*b=,num2str(a*b)disp(a/b=,num2str(a/b)lt12a+b=4-2ia-b=-2+6ia*b=11+2ia/b=-0.2+0.4i例题1.3functionz=lt13x=(-3.5)*pi/180;y=6.7*pi/180;z=sin(abs(x)+abs(y)/sqrt(cos(abs(x+y);lt13ans=0.1772例题1.4functionp1=lt14r=0.0107;n=2015-2000;p0=12.9