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SolveAnOddPowerOfASineOverAPowerOfABinomialInTheSquaredTangentUnderTheCosine​(AngouriMath.​Entity,​AngouriMath.​Entity.​Variable)

 Method (no overloads)

Summary

An odd power of a sine over a whole power of a + b tan(y)^2, under
u = cos(y): a + b tan(y)^2 = ((a - b) u^2 + b)/u^2 and
sin(y)^m dy = -(1 - u^2)^((m - 1)/2) du, so the integrand is the rational
function -(1 - u^2)^((m - 1)/2) u^(2 n)/((a - b) u^2 + b)^n, asked with
a - b named by a symbol of its own and written back into the answer.

Remarks

Bioche's substitution, which comes after the substitution search: the search ran out
of time on Rubi's 4.3.7 sin(e + f x)^3/(a + b tan(e + f x)^2)^3, and took
fifteen seconds on sin^5/(a + b tan^2)^3. The rational function with
a - b written in it took seven seconds, where named it takes a tenth of one.
The quadratic has no linear term, so the name hides no relation between its
coefficients; a = b is another shape, and declines.
https://github.com/asc-community/AngouriMath/issues/233

























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