# Complex DifferentiationWatch

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#1
Any help with this question would be highly appreciated,

Find the x-coordinates of the stationary points of
y=x^3 e^-kx, where k is a positive constant.

Thanks
0
5 years ago
#2
Have you encountered the product and chain rules of differentiation yet?

0
#3
(Original post by Khallil)
Have you encountered the product and chain rules of differentiation yet?

I have used the product rule to get to this stage,

dy/dx=x^3(-ke^-kx)+e^-kx(3x^2)

I am unsure what to do from now onwards
0
5 years ago
#4
(Original post by SimonHackland)
I have used the product rule to get to this stage,

dy/dx=x^3(-ke^-kx)+e^-kx(3x^2)

I am unsure what to do from now onwards
Stationary points occur when the derivative of a function is 0.

You should also note that so you can factor that out and omit it since it doesn't have any real solutions.
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#5
I have done it now, thanks for the help
0
5 years ago
#6
(Original post by SimonHackland)
I have done it know, thanks for the help

*now
0
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