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iamtrojan3
Dec14-09, 04:17 PM
1. The problem statement, all variables and given/known data
this problem was on my finals and i stared at it for 30 mins straight and still didn't figure it out and now it just bothers me that i don't know how to do the first problem on my final exam.

"find the general solution to the dfq"
xy'+xy= 1-y


2. Relevant equations


3. The attempt at a solution
i dont think its linear cause if you do the integrating factor the right side is interms of x and y
i don't think its separable... or multiplying by 1/x and subbing v for y/x could help
i don't think its exact? or is it im not sure
bernouli's formula wont help here.
i don't know its probably something really stupid and easy... thanks for the help!

Dick
Dec14-09, 04:47 PM
The y doesn't have to be on the right side. Write it as x*y'+(x+1)*y=1. Now divide by x and find the integrating factor.

iamtrojan3
Dec14-09, 06:24 PM
OH MY GOD. there goes 20 points that i should of gotten. thank you for the helpe.