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

 Method (no overloads)

Summary

The reciprocal of a + b s^n, s a sine or a cosine of a linear and a symbol in
a or b, over the roots of the binomial: with q = 2 for an even n and 1 for an odd one, m = n/q and r_k the m-th roots of
-a/b, 1/(a + b s^n) = (1/(m a)) sum r_k/(r_k - s^q), and each term is an
arctangent of tan(y) or of tan(y/2).

Remarks

Each term is written F(K u)/K with only K^2 fixed, so its derivative is the
same whichever root K is: (atan(K tan(y))/K)' = 1/(cos(y)^2 + K^2 sin(y)^2).
A root that makes K^2 zero or infinite -- 1/(1 + sin(y)^5) has -1 -- is
another shape, and declines. n up to 4, and numbers for a and
b, are answered by the rules before it. Rubi's 4.1.7 and 4.2.7
1/(a + b sin(x)^5), 1/(a - b cos(x)^6) and the like were declined.
https://github.com/asc-community/AngouriMath/issues/718

Summary

SolveAReciprocalOfABinomialInAPowerOfASineOverItsRoots(AngouriMath.Entity,AngouriMath.Entity.Variable) asked first where a power of
the function stands above or below the binomial: the rules before it in the dispatcher spent
the budget on `sinh(y)^4/(a + b sinh(y)^3)`, and the bare reciprocal they answer is left to them.

























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