Finding the limit $ \lim_{x\to 0}\frac{(1-3x)^\frac{1}{3} -(1-2x)^\frac{1}{2}}{1-\cos(\pi x)}$ I cannot find this limit: 
$$
\lim_{x\to 0}\frac{(1-3x)^\frac{1}{3} -(1-2x)^\frac{1}{2}}{1-\cos(\pi x)}.
$$
Please, help me. 
Upd: I need to solve it without L'Hôpital's Rule and Taylor expansion.

l'Hospital:
$$\lim_{x\to 0}\frac{(1-3x)^{1/3}-(1-2x)^{1/2}}{1-\cos \pi x}\stackrel{\text{l'H}}=\lim_{x\to 0}\frac{-(1-3x)^{-2/3}+(1-2x)^{-1/2}}{\pi\sin\pi x}\stackrel{\text{l'H}}=$$
$$=\lim_{x\to 0}\frac{-2(1-3x)^{-5/3}+(1-2x)^{-3/2}}{\pi^2\cos\pi x}=-\frac1{\pi^2}$$
