Discrete Time Signals and Systems on Digital Signal Processing related Questions and Answers

Question :   Determine the impulse response for the cascade of two LTI systems having impulse responses h1(n)=(1/2)2 u(n) and h2(n)= (1/4)2 u(n). 1. (1/2)n[2-(1/2)n], n<0 2. (1/2)n[2-(1/2)n], n>0 3. (1/2)n[2+(1/2)n], n<0 4. (1/2)n[2+(1/2)n], n>0 Answer :   2 - (1/2)n[2-(1/2)n], n>0