A. a = 2,b = 8 B. a = 2,b = 5 C. a =

免费考试题库2019-12-17  3

问题 A. a = 2,b = 8 B. a = 2,b = 5 C. a = 0,b = -8 D. a = 2,b = -8

选项

答案D

解析正确答案是D。提示:当x→2,分母极限为零,分子也必须为零,故有4 + 2a + b = 0;利用洛必达法则,[img]/upload/tiku/36/2208192_1.jpg[/img]所以a=2,代入4 + 2a + b= 0有b=-8。
转载请注明原文地址:https://ti.zuoweng.com/ti/44oNKKKQ