Question

求函数f（x）=x分之e的x次方的单调区间

Answer 1

f(x)=(e^x)/x
f'(x)=[(e^x)x-e^x]/x^2
令f'(x)>=0
[(e^x)x-e^x]/x^2>=0
解得x>=1
所以函数的单调增区间为[1,正无穷)
令f'(x)