# A Random Walk

Brilli the ant decides to have a walk along an infinitely long 1D line. For each step he takes, he would either walk forward or backwards by a distance of 1 with equal probability. Given that the expected displacement Brilli the ant would travel after $$k$$ steps is $$E_k$$, find

$\lim _{ k\to\infty }{ \frac{2k}{E_k^2} }$

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