x=0:0.01:2*pi;
t=-pi/3:0.02:pi/3;
y1=sin(x);
y2=cos(x);
y3=tan(t);
z=-pi/8:0.02:pi*7/8;
y4=cot(z);
subplot(2,2,1),plot(x,y1),grid on,title('y=sinx')
subplot(2,2,2),plot(x,y2),grid on,title('y=cosx')
subplot(2,2,3),plot(t,y3),grid on,title('y=tanx')
subplot(2,2,4),plot(z,y4),grid on,title('y=cotx')
在matlab中输入上述的就行了