For the problem shown below, $($a$)$ calculate the supporting reaction, $($b$)$ plot the shear force diagram and the

bending moment diagram.

Answer: $($a$)R=\frac{L}{}$

$($b$)F=-\frac{L}{}sin(\frac{x}{L}),M=(\frac{L}{}{)}^{2}cos(\frac{x}{L})$

I don't understand the steps and reasons behind, especially the non$-$uniform load.