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Old 11-29-2007, 07:46 PM
jay_shark jay_shark is offline
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Join Date: Sep 2006
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Default Re: Antiderivative problem

int[1000x/(x^2+16)]dx is ln(x^2+16)*500

Now we check that the derivative of ln(x^2+16)*500 =1000x/(x^2+16)

Since we know that the derivative of lnx =1/x , then the derivative of ln(x^2+16) = 1/(x^2+16)*2x . Now if we multiply 2x by the constant 500 we get 1000x .
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