Please help!
Consider the function f(x)=(x^2)(e^4x)
f(x) has two inflection points at x=c and x=d with c less than or equal to d

Question

Please help!
Consider the function f(x)=(x^2)(e^4x)
f(x) has two inflection points at x=c and x=d with c less than or equal to d

babyslapmafro · Answer

What are you trying to find?

anonymous · Answer

The inflection points of the function. I think you have to take the second derivative to find them but I am having trouble doing that.

babyslapmafro · Answer

take the first derivative
$$f'(x)=2e ^{4x}x(2x+1)$$

babyslapmafro · Answer

ok...are you instructed to use the second derivative or can you use any method...

babyslapmafro · Answer

?

anonymous · Answer

could you use product rule here or would you be able to use chain rule?

babyslapmafro · Answer

to do what?

anonymous · Answer

So when you find the second derivative f"(x)=[(4e^4x)x]+[(2x+1)(4e^4x)] right?

babyslapmafro · Answer

You use both the product and chain rule when finding the second derivative of this function

anonymous · Answer

I am stuck on how to do that could you please help explain it?

babyslapmafro · Answer

product rule:
f'(x)=h'(x)g(x)+h(x)g'(x)

babyslapmafro · Answer

for the second derivative...

h(x)=2e^4x
g(x)=x(2x+1)

babyslapmafro · Answer

or you can set it up using two product rules like this...

babyslapmafro · Answer

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