(25 points) A 4-node, 3-element planar truss is given as below: E, A same for all elements I 1.0 m 0.5 m 0.5 m 2 2P (3) 3P Note that E and A are given symbolically, and are the same for all elements. The length dimensions are as indicated in the figure, and the applied loads are shown in the figure also. You need to use the same node-numbering and element-numbering, as shown in this figure. Using the Method-2 for truss finite element method, i.e., using the 44 [Ke] matrix given at the top of the given formula sheet, obtain the reduced system of finite element matrix equations for this system. Again, just derive the reduced system of equations - no need to solve it. cos Be sin 20 - cos e - sin 20 E.A. sin 20 sin e - sin 20 -sin e [K]= he - - cos 0 -sin 20, cos Be sin 20 sin 20 - sin e sin 20 sine 1-1-3()+2()--(1) he he he * = (A) - 2 (A) = [(A) - *] =3 -2 6 -3he -6 -3he 2Eele -3he 2h2 3h, h2 he [Ke]= h -6 3he 6 3he -3he h 3he 2h2 6 gehe -he 22 {Fe} = + 12 6 23 he 24