Evaluate the following integrals:

∫ x cos3 x2 sin x2 dx

Let cosx2 = t


Then d(cosx2) = dt


Since d(xⁿ) = nxⁿ1 and d(cos x) = -sinx dx


dt = 2x (-sin x2) = -2x sin x2 dx


x sin x2dx =


hence ∫ x cos3 x2 sin x2 dx =


=


=


=


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