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

 Method (no overloads)

Summary

A power of a constant multiple of a radicand that a logarithm holds under a root,
written over that radicand: acosh(c x) is ln(c x + sqrt(c^2 x^2 - 1)),
and beside it d - c^2 d x^2 is -d (c^2 x^2 - 1). A whole power is the
product of the powers; a root (lambda M)^(k/2) is K^k M^(k/2) with
K = sqrt(lambda M)/sqrt(M), which is constant wherever it is defined -- plus or
minus i, or plus or minus sqrt(lambda) -- so it stands in front of the
answer the way Rubi writes it.

Remarks

The substitution u = acosh(c x) needs the root its derivative carries,
sqrt(c^2 x^2 - 1); written over 1 - c^2 x^2 the integrand is the same
function times i and nothing reads it: acosh(a x)^2/sqrt(1 - a^2 x^2) ran
out of time where acosh(a x)^2/sqrt(a^2 x^2 - 1) takes a third of a second, and
x (a + b acosh(c x))/(d - c^2 d x^2)^3 -- a whole power, no root at all -- the same.
K is carried through the integration as a symbol: it is constant, so an
antiderivative in it is one in x once it is written out, whatever the branches.
https://github.com/asc-community/AngouriMath/issues/718

























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