$$\lim_{x \rightarrow 0}\frac{x^2 \sin(Kx)}{x - \sin x} =1$$
Here K is a constant whose value I want to find,
I got it by writing the series expansion of $\sin(\theta)$, but couldn't by L'hospital rule or standard limits,
This is what I tried:
$$\lim_{x \rightarrow 0}\frac{x^2 \sin(Kx)}{x - \sin x} =1$$
$$\implies \lim_{x \rightarrow 0}\frac{x \sin(Kx)}{1 - \frac{\sin x} x} =1$$
$$\implies \lim_{x \rightarrow 0}\frac{Kx^2 \frac{\sin(Kx)}{Kx}}{1 - \frac{\sin x} x} =1$$
So this gives a 0 in the denominator which doesn't help, L'hospital gives a huge mess, applying it once more didn't help
The answer given is K =1/6.
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