S will be my integral sign. Find the derivative of this:(adsbygoogle = window.adsbygoogle || []).push({});

S(from -x to x) e^(-(t)^2) dt

I found it to be 2e^(-x^2)

My teacher says it is 4xe^(-x^2), or maybe a negative in front of the 4 (I forgot), which is also what the math book she got it out of says.

I don't really agree with this solution.. Which is right? (I graphed it and it looked to be what I got for an answer, but I may have done something wrong) I got it counted wrong for a test and I tried to explain my way, but my teacher said it wasn't the right way :[ Another thing I thought was wrong with the books answer is that the integral is always increasing.. so wouldn't the derivative always be positive? (which would count the book's answer wrong because for a negative number for x, it says the function would be decreasing at that point)

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# Derivative of integral

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