Average Error: 41.4 → 41.4
Time: 27.4s
Precision: 64
Internal Precision: 128
\[\frac{2}{1 + e^{-2 \cdot x}} - 1\]
\[{e}^{\left(\log \left(\left(1 + \left(e^{-4 \cdot x} - e^{-2 \cdot x}\right)\right) \cdot \frac{2}{1 + {\left(\sqrt{e^{-2 \cdot x}}\right)}^{3} \cdot {\left(\sqrt{e^{-2 \cdot x}}\right)}^{3}} - 1\right)\right)}\]

Error

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Derivation

  1. Initial program 41.4

    \[\frac{2}{1 + e^{-2 \cdot x}} - 1\]
  2. Using strategy rm
  3. Applied add-exp-log41.4

    \[\leadsto \color{blue}{e^{\log \left(\frac{2}{1 + e^{-2 \cdot x}} - 1\right)}}\]
  4. Using strategy rm
  5. Applied flip3-+41.4

    \[\leadsto e^{\log \left(\frac{2}{\color{blue}{\frac{{1}^{3} + {\left(e^{-2 \cdot x}\right)}^{3}}{1 \cdot 1 + \left(e^{-2 \cdot x} \cdot e^{-2 \cdot x} - 1 \cdot e^{-2 \cdot x}\right)}}} - 1\right)}\]
  6. Applied associate-/r/41.4

    \[\leadsto e^{\log \left(\color{blue}{\frac{2}{{1}^{3} + {\left(e^{-2 \cdot x}\right)}^{3}} \cdot \left(1 \cdot 1 + \left(e^{-2 \cdot x} \cdot e^{-2 \cdot x} - 1 \cdot e^{-2 \cdot x}\right)\right)} - 1\right)}\]
  7. Simplified41.4

    \[\leadsto e^{\log \left(\frac{2}{{1}^{3} + {\left(e^{-2 \cdot x}\right)}^{3}} \cdot \color{blue}{\left(1 + \left(e^{x \cdot -4} - e^{-2 \cdot x}\right)\right)} - 1\right)}\]
  8. Using strategy rm
  9. Applied add-sqr-sqrt41.4

    \[\leadsto e^{\log \left(\frac{2}{{1}^{3} + {\color{blue}{\left(\sqrt{e^{-2 \cdot x}} \cdot \sqrt{e^{-2 \cdot x}}\right)}}^{3}} \cdot \left(1 + \left(e^{x \cdot -4} - e^{-2 \cdot x}\right)\right) - 1\right)}\]
  10. Applied unpow-prod-down41.4

    \[\leadsto e^{\log \left(\frac{2}{{1}^{3} + \color{blue}{{\left(\sqrt{e^{-2 \cdot x}}\right)}^{3} \cdot {\left(\sqrt{e^{-2 \cdot x}}\right)}^{3}}} \cdot \left(1 + \left(e^{x \cdot -4} - e^{-2 \cdot x}\right)\right) - 1\right)}\]
  11. Using strategy rm
  12. Applied pow141.4

    \[\leadsto e^{\log \color{blue}{\left({\left(\frac{2}{{1}^{3} + {\left(\sqrt{e^{-2 \cdot x}}\right)}^{3} \cdot {\left(\sqrt{e^{-2 \cdot x}}\right)}^{3}} \cdot \left(1 + \left(e^{x \cdot -4} - e^{-2 \cdot x}\right)\right) - 1\right)}^{1}\right)}}\]
  13. Applied log-pow41.4

    \[\leadsto e^{\color{blue}{1 \cdot \log \left(\frac{2}{{1}^{3} + {\left(\sqrt{e^{-2 \cdot x}}\right)}^{3} \cdot {\left(\sqrt{e^{-2 \cdot x}}\right)}^{3}} \cdot \left(1 + \left(e^{x \cdot -4} - e^{-2 \cdot x}\right)\right) - 1\right)}}\]
  14. Applied exp-prod41.4

    \[\leadsto \color{blue}{{\left(e^{1}\right)}^{\left(\log \left(\frac{2}{{1}^{3} + {\left(\sqrt{e^{-2 \cdot x}}\right)}^{3} \cdot {\left(\sqrt{e^{-2 \cdot x}}\right)}^{3}} \cdot \left(1 + \left(e^{x \cdot -4} - e^{-2 \cdot x}\right)\right) - 1\right)\right)}}\]
  15. Simplified41.4

    \[\leadsto {\color{blue}{e}}^{\left(\log \left(\frac{2}{{1}^{3} + {\left(\sqrt{e^{-2 \cdot x}}\right)}^{3} \cdot {\left(\sqrt{e^{-2 \cdot x}}\right)}^{3}} \cdot \left(1 + \left(e^{x \cdot -4} - e^{-2 \cdot x}\right)\right) - 1\right)\right)}\]
  16. Final simplification41.4

    \[\leadsto {e}^{\left(\log \left(\left(1 + \left(e^{-4 \cdot x} - e^{-2 \cdot x}\right)\right) \cdot \frac{2}{1 + {\left(\sqrt{e^{-2 \cdot x}}\right)}^{3} \cdot {\left(\sqrt{e^{-2 \cdot x}}\right)}^{3}} - 1\right)\right)}\]

Runtime

Time bar (total: 27.4s)Debug logProfile

herbie shell --seed 2018255 
(FPCore (x y)
  :name "Logistic function from Lakshay Garg"
  (- (/ 2 (+ 1 (exp (* -2 x)))) 1))