∫(x(adsbygoogle = window.adsbygoogle || []).push({}); ^{2}+ 7x) cosx dx

If I make v = (x^{2}+ 7x) and du = cosx dx I get

((x^{2}+ 7x) sinx)/2

If I make v = cosx and du = (x^{2}+ 7x) dx I get

((x^{3}/3 + 7x^{2}/2) cosx)/2

using the form X=Y-X to X=Y/2

Neither are correct, what did I do wrong?

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# Integration by parts is wrong

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