A simple beam ABCDE supports a uniform load of intensity q (see figure). The moment of inertia

Question:

A simple beam ABCDE supports a uniform load of intensity q (see figure). The moment of inertia in the central part of the beam (BCD) is twice the moment of inertia in the end parts (AB and DE). Find the deflection δC at the midpoint C of the beam. (Obtain the solution by using the modified form of Castigliano's theorem.)