max233

I'm checking my solution with WolfRam and it's not matching. I can't see where I'm going wrong, anything obvious I'm missing?

Differential equation:
$\displaystyle 3y''+y'-2y=4+2x+e^x$

Initial conditions:
$\displaystyle y(0)=3, y'(0)=2$

My working:
working_1.jpg
working_2.jpg

studiot

You should check by substituting your solution into the original differential equation to see whether

$\displaystyle 3y'' + y' - 2y$
does indeed equal

$\displaystyle 4 + 2x + {e^x}$

I'm not sure it does, but it is a deal of arithmetic and I might just as easily have made a mistake there as you.

skipjack

I submitted the problem to W|A and its answer was equivalent to yours.