1.
Let f:RRf: \mathbb{R} \to \mathbb{R} be a differentiable function satisfying f(3)+f(2)=0f'(3) + f'(2) = 0. Then limx0(1+f(3+x)f(3)1+f(2x)f(2))1x\displaystyle \lim_{x \to 0} \left( \frac{1 + f(3+x) - f(3)}{1 + f(2-x) - f(2)} \right)^{\frac{1}{x}} is equal to