Error

Derivation

1. Initial program 0.0

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

2. Simplified0.0

   \[\leadsto \color{blue}{e^{(x \cdot x + -1)_*}}\]
3. Using strategy rm

4. Applied fma-udef0.0

   \[\leadsto e^{\color{blue}{x \cdot x + -1}}\]

5. Applied exp-sum0.0

   \[\leadsto \color{blue}{e^{x \cdot x} \cdot e^{-1}}\]
6. Using strategy rm

7. Applied add-log-exp0.0

   \[\leadsto e^{\color{blue}{\log \left(e^{x}\right)} \cdot x} \cdot e^{-1}\]

8. Applied exp-to-pow0.0

   \[\leadsto \color{blue}{{\left(e^{x}\right)}^{x}} \cdot e^{-1}\]

9. Final simplification0.0

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

Reproduce

herbie shell --seed 2019090 +o rules:numerics
(FPCore (x)
  :name "exp neg sub"
  (exp (- (- 1 (* x x)))))