\frac{x + 1}{1 - x}\frac{\sqrt[3]{x + 1} \cdot \sqrt[3]{x + 1}}{\sqrt[3]{1 - x} \cdot \sqrt[3]{1 - x}} \cdot \frac{\sqrt[3]{x + 1}}{\sqrt[3]{1 - x}}(FPCore (x) :precision binary64 (/ (+ x 1.0) (- 1.0 x)))
(FPCore (x) :precision binary64 (* (/ (* (cbrt (+ x 1.0)) (cbrt (+ x 1.0))) (* (cbrt (- 1.0 x)) (cbrt (- 1.0 x)))) (/ (cbrt (+ x 1.0)) (cbrt (- 1.0 x)))))
double code(double x) {
return (x + 1.0) / (1.0 - x);
}
double code(double x) {
return ((cbrt(x + 1.0) * cbrt(x + 1.0)) / (cbrt(1.0 - x) * cbrt(1.0 - x))) * (cbrt(x + 1.0) / cbrt(1.0 - x));
}



Bits error versus x
Results
Initial program 0.0
rmApplied add-cube-cbrt_binary64_23760.7
Applied add-cube-cbrt_binary64_23760.1
Applied times-frac_binary64_24000.1
Final simplification0.1
herbie shell --seed 2020270
(FPCore (x)
:name "Prelude:atanh from fay-base-0.20.0.1"
:precision binary64
(/ (+ x 1.0) (- 1.0 x)))