Average Error: 0.0 → 0.0
Time: 973.0ms
Precision: binary64
\[\cos \left(2 \cdot \cos^{-1} x\right)\]
↓
\[\cos \left(2 \cdot \cos^{-1} x\right)\]
\cos \left(2 \cdot \cos^{-1} x\right)
↓
\cos \left(2 \cdot \cos^{-1} x\right)
double code(double x) {
	return ((double) cos(((double) (2.0 * ((double) acos(x))))));
}
↓
double code(double x) {
	return ((double) cos(((double) (2.0 * ((double) acos(x))))));
}

Error

Bits error versus x

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Derivation

  1. Initial program 0.0

    \[\cos \left(2 \cdot \cos^{-1} x\right)\]

  2. Final simplification0.0

    \[\leadsto \cos \left(2 \cdot \cos^{-1} x\right)\]

Reproduce

herbie shell --seed 2020153 
(FPCore (x)
  :name "(cos (* 2 (acos x)))"
  :precision binary64
  (cos (* 2.0 (acos x))))