How do you use variation parameters to find a general solution if you are given $\displaystyle y_1$ and $\displaystyle y_2$ are linearly independent. Where t>0

$\displaystyle

t^2y''-4ty'+6y=t^{3}+1
y_1 = 5t-1
y_2 = e^{-5t}
$

$\displaystyle

ty''+(1-2t)y' +(t-1)y = te^t
y_1 = e^t
y_2 = e^{t} ln t
$

Thanks CB for the LaTex lesson!!!