876 (a) For springs of spring constants k, and k2 joined end-to-end, show that the LLLLLL equivalent k of the combination spring is: keq = k k2 * 1 + k 2 (Hint: Let X1 and x2 be the distances stretched by each) (b) Show by integrating the work done in stretching the combination spring that when the combination spring is stretched a distance x, the potential energy of the spring is: 1/2 Keqx Prove that this is the same as 1/2 kiX1 +1/2 k2x2-, where x1 and x2 are the distances stretched by each spring in the combination spring