I need your valued precious advice and help once again, in correcting my tutorial homework examples.

Please can you check my work if I am correct or advice where I am going wrong.

gracias

Q1)

If the signal

*x(t)=4cos(200πt)*is sampled at 500 Hz, determine the signal x(n).

What is the period of the sampled signal?

**MY ANSWER:**

*x(t)=4cos((200/500)πt)*

*so my signal x(n) = 4cos((2/5)πt)*

*P = 2π/w*

*Where w is the angular velocity = 2π/5*

*P = 2π/(2π/5) = 5 units*

*So Period is 5 units*

Q2)

Determine the minimum sampling rate to avoid aliasing for the signal

*x(t)=20cos(400πt)+10cos(20πt)*.

**MY ANSWER:**

I will take the highest frequency to avoid aliasing.

So

*P = 2π/w = 2π/400π = 1/200*

*Therefore f= 1/T = 1/(1/200) = 200hz*

*To avoid aliasing fx2 = 400hz*