PVA∞ = A(1 + k)-1 + A(1 + k)-2+..... + A(1 + k)∞ + 1+ A (1 + k)∞
Multiplying both the sides of Eq (a7) by (1+k) provides:
PVA∞ = (1 +k) = A(1 +k) +A (1 +k)-1 +......A (1 +k)-∞ + 2 +A(1 + k)-∞ +1
Subtracting Eq (a7) from eq (a8) provides:
PVA∞ k = A [1 - (1 + k)∞ ]
As (1 + k)-∞ → o eq.(a8) turns into:
PVA∞ k = A
⇒ PVA∞ = A/k