Error

Derivation

1. Initial program 0.2

   \[\left(\frac{m \cdot \left(1 - m\right)}{v} - 1\right) \cdot m\]

2. Simplified0.2

   \[\leadsto \color{blue}{\frac{m}{v} \cdot \left(m - m \cdot m\right) - m}\]
3. Using strategy rm

4. Applied sub-neg0.2

   \[\leadsto \frac{m}{v} \cdot \color{blue}{\left(m + \left(-m \cdot m\right)\right)} - m\]

5. Applied distribute-lft-in0.2

   \[\leadsto \color{blue}{\left(\frac{m}{v} \cdot m + \frac{m}{v} \cdot \left(-m \cdot m\right)\right)} - m\]

6. Applied associate--l+0.2

   \[\leadsto \color{blue}{\frac{m}{v} \cdot m + \left(\frac{m}{v} \cdot \left(-m \cdot m\right) - m\right)}\]

7. Final simplification0.2

   \[\leadsto m \cdot \frac{m}{v} + \left(\left(m \cdot m\right) \cdot \left(-\frac{m}{v}\right) - m\right)\]

Reproduce

herbie shell --seed 2019090 
(FPCore (m v)
  :name "a parameter of renormalized beta distribution"
  :pre (and (< 0 m) (< 0 v) (< v 0.25))
  (* (- (/ (* m (- 1 m)) v) 1) m))