..:: Z transform and its Application on Digital Signal Processing related Questions and Answers

Z transform and its Application on Digital Signal Processing related Questions and Answers

Question : What is the unit step response of the system described by the difference equation
y(n)=0.9y(n-1)-0.81y(n-2)+x(n) under the initial conditions y(-1)=y(-2)=0?
1. [1.099+1.088(0.9)ⁿ.cos(πn/3+5.2^o)]u(n)
2. [1.099+1.088(0.9)ⁿ.cos(πn/3-5.2^o)]u(n)
3. [1.099+1.088(0.9)ⁿ.cos(πn/3-5.2^o)].
4. None of the mentioned
Answer : 2 - [1.099+1.088(0.9)ⁿ.cos(πn/3-5.2^o)]u(n)