时间0-1，0.0001间隔，产生一个频率为1，振幅1的sin，然后产生一个频率为1000，振幅1的cos,两个相乘，相加，以子图展示这两个图，给出matlab代码

t = 0:0.0001:1; x1 = sin(2*pi*t); x2 = cos(2*pi*1000*t); x3 = x1.*x2; x4 = x1+x2; subplot(2,1,1); plot(t,x1,'r'); hold on; plot(t,x2,'b'); legend('sin','cos'); title('Sin and Cos Waves'); subplot(2,1,2); plot(t,x3,'g'); hold on; plot(t,x4,'m'); legend('sin*cos','sin+cos'); title('Multiplication and Addition of Sin and Cos Waves');