고체역학 (Gere) — Shear Forces and Bending Moments: Problem 4.3-25

4.3-25 Frame $ABC$ has a moment release just left of joint $B$. Find axial force $N$, shear force $V$, and moment $M$ at the top of column $AB$. Write variables $N, V$, and $M$ in terms of variables $P$ and $L$.