# Inspired by Surya Prakash

Calculus Level 3

$\large \dfrac {1 \times 2}{a} + \dfrac {2 \times 3}{a^2} + \dfrac {3 \times 4}{a^3} + \dfrac {4 \times 5}{a^4} + \ldots$

Find the value of the above expression provided $$|a|>1$$ and if it continues ad infinitum.

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