f (x )=ex+1/ex,证明f(x)在(0,+00)上是增函数

问题描述:

f (x )=ex+1/ex,证明f(x)在(0,+00)上是增函数

对f (x )=ex+1/ex求导得f' (x )=(e-1)/(e^2 )x大于0,所以f(x)在(0,+00)上是增函数,

设01
因为a