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View Full Version : Need Help with a Dif Eq


hakett86
08-26-2006, 08:32 PM
hi there i need help trying to solve:

(e^x) dy/dx = y-ye^x , y(0) = 2

please any hints will help!!!

OfficeShredder
08-27-2006, 02:03 AM
Try a separation of variables:

e^x*dy/dx = y(1-e^x)

dy/dx=y(1-e^x)/e^x

dy/y=(1-e^x)/e^x dx

I'm not sure if this is the best way to do it, but it looks solvable this way (integrate both sides from here)

Jameson
08-28-2006, 12:43 AM
That's definitely the best way to do it. Break up (1-e^x)/e^x into (1/e^x)-e^x/e^x or more simply e^(-x)-1.

lozygo
06-26-2008, 02:18 AM
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[size=2] There are balms for all our pain:
But when youth, the dream, departs
It takes something from our hearts,
And it never comes again.
We are stronger, and are better,
Under manhood's sterner reign:
Still we feel that something sweet
Followed youth, with flying feet,
And will never come again.
Something beautiful is vanished,
And we sigh for it in vain;
We behold it everywhere,
On the earth, and in the air,
But it never comes again!