My Lecturer give me this problems, help please,

...not all, .. one number is all right, at least I'll get an example to solve the other ....

$\displaystyle

\begin{gathered}

1).\frac{{dy}}

{{dx}} + 3\frac{y}

{x} = 6x^2 \hfill \\

2).((\cos ^2 x - y\cos x))dx - (1 + \sin x)dy = 0 \hfill \\

3).x^2 \frac{{dy}}

{{dx}} + xy = xy^3 \hfill \\

4).\frac{{d^2 y}}

{{dx^2 }} - 2\frac{{dy}}

{{dx^{} }} - 3y = 2e^x - 10\sin x \hfill \\

5).\frac{{d^2 y}}

{{dx^2 }} + y = \tan x\sec x \hfill \\

\end{gathered}

$

Thank you very much