the integral of 2tan^{4}xdx or rewritten: integral of 2(tanx)^{4} dx

Hi Nicole,

Use the trigonometric identity

1 + tan^{2}x = sec^{2}x

and write

tan^{4}x = (tan^{2}x)^{2} = (sec^{2}x - 1)^{2} = sec^{4}x - 2 sec^{2}x + 1

Can you integrate this expression?

Penny

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