Question

用Matlab怎么画给定函数的图像呢？

x是取自随机数0～9的，得到一个方程k=4.6651-0.5074x^4+8.1055x^3-40.6303x^2+90.2343x;可是怎么画出他的曲线图呢？还可以得到另外两个曲线图，怎么把他们画在一张图上呢？万分感谢！急！急！急！

Answer 1

syms x x0
k=4.6651-0.5074*x.^4+8.1055*x.^3-40.6303*x.^2+90.2343*x
%subplot(m,n,i)生成m×n个子图窗口，i是每个窗口的index
%%%%%%%%%%%%%%%%%%%%%%%%%%
subplot(3,2,1);%1
ezplot(k);
hold on
x0=ceil(9*rand)
%k0=str2num(subs(k,x,x0))
plot(double(x0),subs(k,x,x0),'ro');hold off
%%%%%%%%%%%%%%%%%%%%%%%%%%
subplot(3,2,2);%2
ezplot('sin(x)'); %
%%%%%%%%%%%%%%%%%%%%%%%%%%
subplot(3,2,3);%3
ezplot('cos(x)');
%%%%%%%%%%%%%%%%%%%%%%%%%%
subplot(3,2,4);%4
ezplot('e^x');
%%%%%%%%%%%%%%%%%%%%%%%%%%
subplot(3,2,[5 6]);%第5和第6个窗口合并
%u=1:0.1:10
plot(1:0.1:10,tan(u),'b')

------------------------
你研究一下