Evaluate limx→0(1x2−1sin2x)\lim_{x \to 0} \left( \frac{1}{x^2} - \frac{1}{\sin^2 x} \right)limx→0(x21−sin2x1).
1/31/31/3
−1/3-1/3−1/3
000
−1/2-1/2−1/2