Quote:
Originally posted by Ilander:
Anyway, so I can't figure out the integral of x sin^2 (x) dx...  ...I've spent two hours thinking about it, and I'm no closer, as integration by substitution seems to get me nowhere...
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I'm probably too late to be useful, but the answer is:
(x^2 / 4) - (1/8 * cos(2x)) - (1/4 * x * sin(2x))
You've to use the identity integral( sin(x)^2 ) == x/2 - 1/4 * sin(2x)
(whew... haven't integrated anything in a while
)