若a=0 定义域x∈R
f(x)=e^X-1-x
f'(x)=e^(x)-1
令f'(x)>0 e^(x)-1>0 e^(x)>1=e^0 x>0
f(x)的单调递增区间为 (0,+无穷)
令f'(x)<0 e^(x)-1<0 e^(x)<1=e^0 x<0
f(x)的单调递减区间为 (-无穷,0)
若a=0
定义域x∈R
f(x)=e^X-1-x
f'(x)=e^(x)-1
令f'(x)>0
e^(x)-1>0
e^(x)>1=e^0
x>0
f(x)的单调递增区间为
(0,+无穷)
令f'(x)<0
e^(x)-1<0
e^(x)<1=e^0
x<0
f(x)的单调递减区间为
(-无穷,0)