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## Homework Statement

Find the length of the curve y=x^2-4|x|-x from x=-4 to x=4.

## The Attempt at a Solution

I realized there is a corner at x=0 so i tried to get around this by pluggin in x for x>=0 and -x for x<0. However, my integrals don't match the answer.

http://texify.com/img/%5CLARGE%5C%21%5CLARGE%5C%21%5Cint_%7B-4%7D%5E%7B0%7D%20%5Csqrt%7B1%2B%282x-3%29%5E2%7D%20dx%20%2B%20%5Cint_0%5E%7B4%7D%20%5Csqrt%7B1%2B%282x-5%29%5E2%7D%20dx%20.gif

Which does not match the answer 19.56, what did I do wrong?

Also, when I do try to find arc length in parametric curves and often more that not, a curve repeats itself in a given interval. How do I detect this and avoid it to just find length of one cycle?

Also, when I do try to find arc length in parametric curves and often more that not, a curve repeats itself in a given interval. How do I detect this and avoid it to just find length of one cycle?

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