Given sin(x)=∑n=0∞(−1)nx2n+1(2n+1)!\sin(x) = \sum_{n=0}^{\infty} \frac{(-1)^n x^{2n+1}}{(2n+1)!}sin(x)=∑n=0∞(2n+1)!(−1)nx2n+1, what is the coefficient of x3x^3x3 in sin(2x)\sin(2x)sin(2x)?
13!\frac{1}{3!}3!1
83!\frac{8}{3!}3!8
−43-\frac{4}{3}−34
43\frac{4}{3}34