设曲线y= x+1 x-1 在点(3,2)处的切线与直线ax+y+3=0垂直,则a=(  ) A.2 B.-2 C

2025-06-22 00:51:41
推荐回答(1个)
回答1:

由题意得,y′=
(x+1)′(x-1)-(x+1)(x-1)′
(x-1 ) 2
=
-2
(x-1) 2

∵在点(3,2)处的切线与直线ax+y+3=0垂直,
-2
(3-1) 2
=
1
a
,解得a=-2,
故选B.