# Math Help - infinity condition on 2nd order diff

1. ## infinity condition on 2nd order diff

so if I have

y"+y'-2y = 0

with y-> as x-> infinity, y(0)= 2

would I proceed here when it comes to the condition?

2. Originally Posted by dankelly07
so if I have

y"+y'-2y = 0

with y-> as x-> infinity, y(0)= 2

would I proceed here when it comes to the condition?
i think you're missing something, y -> what as x -> infinity?

3. Oops yeah ,

with y-> 0 as x-> +infinity, y(0)= 2

4. Originally Posted by dankelly07
Oops yeah ,

with y-> 0 as x-> +infinity, y(0)= 2
The general solution is $y(x)=Ae^x+Be^{-2x}$ (I hope you know why).

If $y \to 0$ as $x \to \infty, A=0$

and you should be able to finish from there.

RonL