Solution:
In $\triangle \mathrm{APB}$ and $\triangle \mathrm{APC}$
$\angle \mathrm{APB}=\angle \mathrm{APC}\left(\right.$ Each $\left.90^{\circ}\right)$
$A B=A C($ Given $)$
$\mathrm{AP}=\mathrm{AP}($ Common $)$
$\therefore \triangle \mathrm{APB} \cong \triangle \mathrm{APC}(\cup$ sing RHS congruence rule $)$
$\Rightarrow \angle B=\angle C$ (By using CPCT)
In $\triangle \mathrm{APB}$ and $\triangle \mathrm{APC}$
$\angle \mathrm{APB}=\angle \mathrm{APC}\left(\right.$ Each $\left.90^{\circ}\right)$
$A B=A C($ Given $)$
$\mathrm{AP}=\mathrm{AP}($ Common $)$
$\therefore \triangle \mathrm{APB} \cong \triangle \mathrm{APC}(\cup$ sing RHS congruence rule $)$
$\Rightarrow \angle B=\angle C$ (By using CPCT)