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Homework Statement
∫ 1/(x√(25-x^2)) dx
Homework Equations
by trigonometic substitution I got the following equations
x = 5 sin θ
dx = 5 cos θ dθ
√(25-x^2) = 5 cos θ
θ = sin^-1 (x/5)
The Attempt at a Solution
I solved it and got the following (so far, it is okay with wolfram alpha):
∫ 1/(x√(25-x^2)) dx = (1/5) ∫ csc θ dθ
according to me, the result should be (1/5) ( ln ( 5/x - √(25-x^2)/x ) )
but according to wolfram alpha it should be (1/5) ( ln (x) - ln ( √(25-x^2) + 5 ) )
are these two results equivalent?