Mark M. answered 10/13/17
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Retired math prof. Calc 1, 2 and AP Calculus tutoring experience.
I don't think that the integral of cosxlnx (I assume that that's what you mean) can be expressed by using standard mathematical functions). At least, that's what Wolfram Alpha says.
The function can be differentiated by using logarithmic differentiation as follows:
y = cosxlnx
lny = ln(cosxlnx)
lny = (lnx)(ln(cosx))
y'/y = (1/x)(ln(cosx)) + (lnx)(-sinx/cosx)
y' = y[(1/x)ln(cosx) - (lnx)(tanx)]
y' = (cosx)lnx [(1/x)ln(cosx) - (lnx)(tanx)]