# how to make a derivative by x..

• August 17th 2009, 01:06 AM
transgalactic
how to make a derivative by x..
$
y'=Ae^y+Be^{-y}+2
$

y is a function of x
$
y'=Ae^y+Be^{-y}+2
$

so
$
y''=Ae^yy'+Be^{-y}y'+2
$
• August 17th 2009, 02:18 AM
CaptainBlack
Quote:

Originally Posted by transgalactic
$
y'=Ae^y+Be^{-y}+2
$

y is a function of x
$
y'=Ae^y+Be^{-y}+2
$

so
$
y''=Ae^yy'+Be^{-y}y'+2
$

I don't know about anwone else but I can't see a question here, what is it you want to do?

CB
• August 17th 2009, 02:19 AM
Mush
If $\frac{dy}{dx} = Ae^y + Be^{-y} + 2$

then,

$\frac{d^2y}{dx^2} = Ae^y \frac{dy}{dx} - Be^{-y} \frac{dy}{dx}$
• August 17th 2009, 02:20 AM
Mush
Quote:

Originally Posted by CaptainBlack
I don't know about anwone else but I can't see a question here, what is it you want to do?

CB

I believe they have been given the 1st derivative, and have been asked to find the second?