The truss ABCD shown in the figure is loaded by a vertical force P at joint Band by a horizontal force P at joint C. The axial rigidity of every member is EA. Determine the vertical displacement δc of joint C. (Hint: Add a vertical load Q at joint c.)
![1486_b53f3d28-6155-4d14-953e-6b1a3f48d9dd.png](https://secure.tutorsglobe.com/CMSImages/1486_b53f3d28-6155-4d14-953e-6b1a3f48d9dd.png)