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majin_andrew
Sep1-09, 01:37 AM
This isn't a homework question, just something I was wondering about, and this seemed like the most appropriate place to post it because of its simplicity.

When integrating a function of the form f(x)=(x-a)^{n}, I find I get a different result if I expand the brackets first and then integrate.

Example:
\int2(x-5)dx = (x-5)^{2} + C = x^{2}-10x-25 + C
\int2x-10dx = x^{2}-10x + C

I was wondering if the C in the first equation will simply just be 25 greater than the C in the second equation, or is there more to it than that?

Thanks for your time,
Andrew

rock.freak667
Sep1-09, 01:56 AM
In your two integrals, the values of 'C' are different. In the first one you have -25 + C, which is in itself another constant k. So you can rewrite it as x2 -10x+k. Which is in the same form as your second integral.

majin_andrew
Sep1-09, 02:14 AM
Thanks rock.freak667!