Deriving the Elastic Energy Equation: How Do I Go from F=kx to F=1/2kx^2?

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To derive the elastic energy equation from F=kx to F=1/2kx^2, one must calculate the work done by the force as the spring compresses or extends. The force varies with displacement, necessitating the use of calculus to integrate the force over the distance from 0 to x. The work done, which represents elastic energy, is equivalent to the area under the force versus displacement graph. This area can be calculated as the integral of F with respect to x. Ultimately, the elastic energy equation is derived as U=1/2kx^2, where U represents elastic potential energy.
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Homework Statement


Derive an equation for elastic energy, in terms of k and x. Show all steps.

Homework Equations


F=1/2kx^2

The Attempt at a Solution


I believe Force=1/2kx^2 is the answer but how would I show steps to get an elastic energy equation? Basically, going from F=kx, what steps do I need to take to go from that equation to the elastic energy equation.
 
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You need to find the work done by the F = kx force as it compresses the spring (or as the spring pushes with that force on some other object). x will vary from 0 (meaning no compression or extension) to some final value X. It would be easy if F didn't vary with x. Since it does vary with x, you will have to use calculus or some kind of workaround. Perhaps you can find a definition of work involving the area under a force graph.
 
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