$($a$)[$Points $\frac{0\mathrm{.}33}{3}$ Method of Sections $($brutal force method$),$

$($b$)[$Points $\frac{0\mathrm{.}33}{3}$ Multiple integration $($equations$)$ method,

$($c$)[$Points $\frac{0\mathrm{.}33}{3}$ Derivative inductions Method.

Please help, hand written answers are preffered.