Calculus

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Evaluate the indefinite integral.
∫ sec^3x tanx dx

I let u=tanx
took derivative..
du=sec^2x dx

..now what??

  • Calculus -

    sec^3 x tan x dx
    | = integral symbol

    Rewrite as
    | sec^2 x sec x tan x dx
    u = sec x
    du = sec x tan x

    | u^2 du
    1/3 u^3 + C

    Substitute back in, u = sec x
    1/3 sec^3 x + C

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