Question Number 189958 by Gbenga last updated on 25/Mar/23
$$\boldsymbol{\mathrm{solve}}\:\boldsymbol{\mathrm{y}}'''−\boldsymbol{{y}}''−{y}={sect}\:\:\:\:\:\:\:\:\left(−\frac{\pi}{\mathrm{2}}<{x}<\frac{\pi}{\mathrm{2}}\right) \\ $$
solve-y-y-y-sect-pi-2-lt-x-lt-pi-2-