Problemlimx→2x2−4x−2\lim_{x \to 2} \frac{x^2 - 4}{x - 2}limx→2x−2x2−4分步解答直接代入得到 00\frac{0}{0}00 —— 不定型。将分子以平方差因式分解：x2−4=(x−2)(x+2)x^2 - 4 = (x - 2)(x + 2)x2−4=(x−2)(x+2)。约去公因式 (x−2)(x - 2)(x−2)：limx→2(x+2)\lim_{x \to 2}(x + 2)limx→2(x+2)。代入：2+2=42 + 2 = 42+2=4。答案444想解其他题？打开 limit 求解器 →相关例题/solve/calculus/limit-of-sin-x-over-x/solve/calculus/limit-of-x2-as-x-approaches-2延伸阅读/blog/limits-and-continuity