How do we evaluate this limit?

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$$ A_N(x) = \lim_{N\to \infty}(\sin(x)/x)^N $$

The solution to this problem is given as,

$$ A_N(x) = \exp( -Nx^2/6). $$

The problem is solved through

  1. Taylor series expansion for $\sin(x)$.
  2. And the famous limit

$$ \lim_{N\to \infty}(1+(x/N))^N = \exp(x). $$

I'm not able to figure out the disappearance of some of the higher degree terms. How exactly is this limit calculated . An insight would be great.

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$\lim_{N\to \infty}(1+(x/N)+ H.O.T.)^N = exp(x)$

where H.O.T. are Higher Order Terms. So you can put the remainder of Taylor series there.

BTW your formula for $A_N(x)$ contains an error. If it's a limit as $N \to \infty$, how can the answer depend on $N$?