What is the partial fraction expansion of X(z)=1/((1+z-1)(1-z-1)2)?a)z...
Explanation: First we express X(z) in terms of positive powers of z, in the form X(z)=z3/((z+1)〖(z-1)〗2 )
X(z) has a simple pole at z=-1 and a double pole at z=1. In such a case the approximate partial fraction expansion is
(X(z))/z = z2/((z+1)〖(z-1)〗2 ) =A/(z+1) + B/(z-1) + C/〖(z-1)〗2
On simplifying, we get the values of A, B and C as 1/4, 3/4 and 1/2 respectively.
Therefore, we get X(z)= z/(4(z+1)) + 3z/(4(z-1)) + z/(2〖(z-1)〗2 ) .
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What is the partial fraction expansion of X(z)=1/((1+z-1)(1-z-1)2)?a)z...
Partial Fraction Expansion Explanation:
Given Function:
X(z) = 1 / ((1 + z - 1)(1 - z - 1)^2)
Partial Fraction Expansion Steps:
1. Factorize the denominator:
(1 + z - 1)(1 - z - 1)^2 = z(1 - z - 1)^2
= z(1 - z + 1)^2
= z(2 - z)^2
2. Write X(z) in partial fraction form:
X(z) = A / (z+1) + B / (z-1) + C / (2 - z)
3. Find the values of A, B, and C:
1 = A(2 - z)^2 + B(z+1)(2 - z) + C(z+1)^2
1 = A(4 - 4z + z^2) + B(2z - z^2 + 2 - z) + C(z^2 + 2z + 1)
4. Solve for A, B, and C:
By comparing the coefficients, we get:
A = 1/4, B = 3/4, C = 1/2
Partial Fraction Expansion:
X(z) = z / (4(z+1)) + 3z / (4(z-1)) + z / (2(2-z))
Therefore, the correct partial fraction expansion of X(z) is option 'C'.