# Thread: Partial derivative of a function with exp in it

1. ## Partial derivative of a function with exp in it

Hi all, I am new here and I hope someone can help with a problem I am having. How can I find the derivative with respect to x of

m(x) = m exp (-x^2/2A^2)

I think what I am looking for is a partial derivative. I have got as far as

dm(x)/dx = (-2x/2A^2) m exp (-x^2/2A^2)

I don't think I need to do anything complex to find the derivative of the (-x^2/2A^2) part of the equation, as it is not in the form f(x)/g(x), rather it is f(x)/"nothing-to-do-with-x"

Is there anything I can do to this formula to make the exp function go away? (I don't want an ln either!)

Many thanks in advance for any help

2. Originally Posted by Celicajunkie100
Hi all, I am new here and I hope someone can help with a problem I am having. How can I find the derivative with respect to x of

m(x) = m exp (-x^2/2A^2)

I think what I am looking for is a partial derivative. I have got as far as

dm(x)/dx = (-2x/2A^2) m exp (-x^2/2A^2)

This is it! Now just simplify and do some order and get $\displaystyle \frac{dm(x)}{dx}=-\frac{mx}{A^2}\,e^{-\frac{x^2}{2A^2}}$

I don't think I need to do anything complex to find the derivative of the (-x^2/2A^2) part of the equation, as it is not in the form f(x)/g(x), rather it is f(x)/"nothing-to-do-with-x"

Is there anything I can do to this formula to make the exp function go away? (I don't want an ln either!)

You can erase it......but for that nothing: the exp. functions stays in its derivative.

Tonio

Many thanks in advance for any help
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