(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

∫ -60x^{3}tan(3x^{4})dx

2. Relevant equations

integration rules

3. The attempt at a solution

=> ∫ -60x^{3}tan(3x^{4})dx

=> u = (3x^{4})

=> du = 12x^{3}dx

=> (-5)∫ (1/5)-60x^{3}tan(3x^{4})dx

=> -5 ∫ tan u

=> -5.-ln cos(u) , where u = (3x^{4})

=> 5.ln cos (3x^{4})

I am using this integral to check an original equation which I differentiated which was:

ln (cos^{5}(3x^{4}) , so where have I gone wrong when integrating, because I'm not getting it back ? ( I have started just learning the basics of integration so be nice :) )

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# Homework Help: Integral please check

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