Find a valueof"a" such that the function

f(x) = x^2e^ax has a critical point at x = -1.

I have no clue how to do this??

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- Oct 27th 2008, 05:52 PMab32solving critical point problems??
**Find a value****of**"**a" such that the function**

**f(x) = x^2e^ax has a critical point at x = -1.**

**I have no clue how to do this??**

- Oct 27th 2008, 06:10 PMKrizalid
Critical points are found by makin' do it.

- Oct 27th 2008, 06:15 PMab32
i dont know how f! when theres a e????

- Oct 28th 2008, 01:02 PMab32
can any one else tell me how to slove this? Please

- Oct 28th 2008, 02:37 PMCakecake
First you find the derivative of it, by using the product rule. If you don't know how to do that then you should start paying attention in class.

I'm almost positive this is right, the derivative of the exponent of e may be wrong. So if it is, can someone kindly point that out.

You can carry on from here. Clean it up a bit to make life easier, then set to equal zero and substitute x then solve for a. - Oct 28th 2008, 03:10 PM11rdc11
- Oct 28th 2008, 03:46 PMab32
thanks for your help i understand how to get the dervi , now how do i use that -1 critical point?

- Oct 28th 2008, 04:27 PM11rdc11
You know you have a critical point when the derivative equals 0. The problem told you the critical point was x = -1 so plug all this into your equation

Now just solve for a