(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

An applied force varies with position according to F = k_{1}x^{n}- k_{2}, where n = 3, k_{1}= 8.3 N/m^{3}, and k_{2}= 87 N. How much work is done by this force on an object that moves from x_{i}= 6.47 m to x_{f}= 14.9 m? Answer in units of kJ.

2. Relevant equations

W = k_{1}x^{4}/4 ]from the integral of x_{1}to x2

- k_{2}x]from x_{1}to x_{2}

3. The attempt at a solution

I plugged in everything, and I got 96.778 at first, then I thought I should use x3^{3}/3, then I got 6.543478 kJ.

I got both them wrong, did I do the calculation wrong? Please help, thanks. :D

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# Homework Help: Simple integration for Work

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