函数y=12(ex+e−x)的导数是(  ) A.12(ex−e−x) B.12(ex+e−x) C.ex-e-x D.ex+e-x

问题描述:

函数y=

1
2
(ex+e−x)的导数是(  )
A.
1
2
(exe−x)

B.
1
2
(ex+e−x)

C. ex-e-x
D. ex+e-x

y=

1
2
(ex+e−x),
∴y′=
1
2
(ex−1×e−x)
=
1
2
(exe−x)

故选A.