Evaluate: `inttan^8xsec^4xdx`

Explanation

Given,

`f(x)=int tan^8xsec^4xdx`

`f(x)=int tan^8xsec^2xsec^2xdx`


`f(x)=int tan^8x(1+tan^2x)sec^2xdx`

`f(x)=int tan^8xsec^2xdx+int tan^10xsec^2xdx`


Let,

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