1. The problem statement, all variables and given/known data Consider a spring with spring constant k = 8.42 N/m with an unstretched length of 0.250 m. How much work do you do on the spring in stretching it from a length of L1 = 0.450 m to a length of L2 = 0.559 m? 2. Relevant equations F= kx W=(1/2) kx^2 3. The attempt at a solution since work is area under the curve of x vs. F graph, I did: W=(1/2)(8.42)(0.559-0.450)^2 = 0.0500 J (wrong answer) wrong maybe because this works only when u start at the unstretched length? So I also tried W= (1/2) k xf^2 - (1/2) k xi^2 [where xf = 0.559 and xi=0.450) =0.464J (still wrong) What am i doing wrong?