The plane truss shown in the figure has two elements and three nodes. Calculate the \(4 \times 4\) element stiffness matrices. Show the row addresses clearly. Derive the final equations (after applying boundary conditions) for the truss in the form of \([\mathbf{K}]\{\mathbf{Q}\}=\{\mathbf{F}\}\). What are nodal displacements and the element forces? Assume:

3 y F 45 L 1 2 45 L X 2