SolveAnEvenQuotientOverAPowerOfABiquadraticBesideAnotherFactorInTheSquare​(AngouriMath.​Entity,​AngouriMath.​Entity.​Variable,​System.​Boolean)

An even rational function with a symbol in it, over a power past the first of a biquadratic of
three terms beside another factor in x^2, split over its written factors in w = x^2 and each
term asked in x. 1/((x^2 - 1)(c + d x^2 + f x^4)^2) is
A/(w - 1) + (B + C w)/Q(w) + (D + E w)/Q(w)^2, and every term is a shape the rules
answer at once; split in x, the series at the roots of x^2 - 1 ran to coefficients
of a hundred thousand nodes, with powers like c^40 f^58, and past the budget. That
is Rubi's 6.1.7 csch(u)/(a - b sinh(u)^4)^2 under w = cosh(u). Checked by
its derivative.
https://github.com/asc-community/AngouriMath/issues/718