Let a vertical tower AB have its end A on the level ground. Let C be the mid-point of AB and P be a point on the ground such that AP =2 AB. If ∠ BPC…

Let a vertical tower AB have its end A on the level ground. Let C be the mid-point of AB and P be a point on the ground such that $\displaystyle \mathrm{AP}=2 \mathrm{AB}$. If $\displaystyle \angle \mathrm{BPC}=\beta$, then $\displaystyle \tan \beta$ is equal to :