[Math] Determining the convergence of $ \sqrt{n} \sin(\pi/\sqrt{n}) $

calculus

I'm trying to find what this function converges to.

$$ \sqrt{n} \sin(π/\sqrt{n}) $$

I've taken the limit:

$$ \lim_{n\rightarrow\infty} \sqrt{n}\sin(π/\sqrt{n}) $$

It appears as though the function takes the following form as n approaches infinity:

\begin{align*}
\lim_{n\rightarrow\infty} \infty \sin(π/\infty) &= \lim_{n\rightarrow\infty} \infty\cdot \sin(0)\\
&= \infty
\end{align*}

I have been told that this converges to $\pi$, which means I'm doing something wrong here. What am I doing wrong?

Best Answer

Recall that $$\lim_{x \to 0} \dfrac{\sin(ax)}{x} = a$$

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