Integrating tan^5(6x) sec^3(6x) - A Guide

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Homework Statement


[tex]\int tan^5(6x) sec^3(6x) dx[/tex]



Homework Equations





The Attempt at a Solution


first off I set u=6x to get 1/6[tex]\int tan^5(u) sec^3(u) dx[/tex]
then I used trig identities to put tangent in terms of secant and I came up with

[tex]\int sec^9(u)-3sec^7(u)+3sec^5(u)-sec^3(u) dx[/tex]
Not sure where to go from here, or if I'm doing this the right way
 
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Watch your substitutions.

[tex]\frac 1 6\int\tan^{5}u\sec^{3}udu[/tex]

[tex]\frac 1 6\int\tan^{4}u\sec^{2}\sec u\tan udu[/tex]

*[tex]\tan^{2}u+1=\sec^{2}u[/tex]

Take it from here.