SOLUTION: f(x)= xe^x the point x. f(x) at which the second derivative equals zero is ???

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Question 1082616: f(x)= xe^x the point x. f(x) at which the second derivative equals zero is ???
Found 2 solutions by Boreal, natolino_2017:
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
f'(x)=x*e^x+e^x=e^x(x+1)
f''(x)=e^x+(x+1)*e^x=e^x(1+x+1)=e^x(x+2)
This equal 0 only if x+2=0 or x=-2
graph of function and second derivative
graph%28300%2C300%2C-10%2C10%2C-1%2C10%2Cx%2Aexp%28x%29%2C%28x%2B2%29%2Aexp%28x%29%29

Answer by natolino_2017(77) About Me  (Show Source):
You can put this solution on YOUR website!
f(x) =x*exp(x)
f'(x) = (x+1)exp(x)
f''(x) = (x+2)exp(x) = 0
(x+2) = 0
x = -2
@natolino_