Frequency Analysis of Signals and Systems on Digital Signal Processing related Questions and Answers

Question :   If h(n) is the impulse response of an LTI system T and h1(n) is the impulse response of the inverse system T-1, then which of the following is true? 1. [h(n)*h1(n)].x(n)=x(n) 2. [h(n).h1(n)].x(n)=x(n) 3. [h(n)*h1(n)]*x(n)=x(n) 4. [h(n).h1(n)]*x(n)=x(n) Answer :   3 - [h(n)*h1(n)]*x(n)=x(n)