# HELP Unit-Impulse Response for Discrete System problem

1. Oct 16, 2006

### Raihan

HELP!!Unit-Impulse Response for Discrete System problem

Compute the unit-pulse response for the discrete time system

1) y[n + 2] + 1/2 y[n+1]+1/4y[n] = x[n+1]-x[n] (for n = 0, 1, 2)
For number 1) the options for right answers are:
a. 0, -1, 2
b. 0, -1, 1/2
c. 0, 1, -3/2
d. 0, 1, 2

2) y[n + 2] + 1/4 y[n+1]-3/8y[n+2] = 2x[n+2]-3x[n](for n = 0, 1, 2)
For number 2) the options for right answers are:
a. 0, -1, 4
b. 2, -1/4, 1/2
c. 0, -1, -3/2
d. 2, -1/2, -17/8

I am completely stuck if you could at least give me the right answer still it will be helpful.

2. Oct 17, 2006

### Staff: Mentor

Show us what you've learned about how to calculate the impulse response of a digital filter, and then we can help you.

3. Oct 17, 2006

### Raihan

Hey I already figured out the second one. None of the answers are right. But and I told my teacher about it and he agreed with me. I am confortable doing impulse response but not this one.
Generally in impulse response we replaceY[n] with h[n] and x[n] with delta[n] and put the n values as given 0,1,2 and find the values for the value of h[n]. first we re arrange the equation for h[n] and then find it. but after finding those values what should I do ? I am stuck right there.
Thanks