Some of your algebra is a bit worrying - check carefully.
Your integral is easy (no chain or product rule to work backwards through, just the power rule) if you start with
Then integrate each term separately.
can some one please check this for me
need to evaluate integral x(7-3x^2) for x=6 to x=4
i did this 1/2(7-3x^2)(2x)dx
then for x=6 to x=4
am i on the right track ?