How do I find the general solution to the equation [math]y^{''}-2y^{'}+2y=e^x+x\cos x[/math]?
How do I prove that [math]Span( { e^{-2x},e^{-x} } )=S[/math] where [math]S[/math] is the space of all solutions to [math]y''+3y'+2y=0[/math]?