Average Error: 30.0 → 0.3
Time: 4.2m
Precision: 64
Internal Precision: 1344
\[\sqrt{x + 1} - \sqrt{x}\]
\[{\left(\sqrt{1 + x} + \sqrt{x}\right)}^{\left(-\frac{1}{2}\right)} \cdot {\left(\sqrt{1 + x} + \sqrt{x}\right)}^{\left(-\frac{1}{2}\right)}\]

Error

Bits error versus x

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Your Program's Arguments

Results

Enter valid numbers for all inputs

Target

Original30.0
Target0.2
Herbie0.3
\[\frac{1}{\sqrt{x + 1} + \sqrt{x}}\]

Derivation

  1. Initial program 30.0

    \[\sqrt{x + 1} - \sqrt{x}\]
  2. Using strategy rm
  3. Applied flip--29.8

    \[\leadsto \color{blue}{\frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \sqrt{x} \cdot \sqrt{x}}{\sqrt{x + 1} + \sqrt{x}}}\]
  4. Using strategy rm
  5. Applied add-log-exp31.7

    \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \color{blue}{\log \left(e^{\sqrt{x} \cdot \sqrt{x}}\right)}}{\sqrt{x + 1} + \sqrt{x}}\]
  6. Applied add-log-exp31.1

    \[\leadsto \frac{\color{blue}{\log \left(e^{\sqrt{x + 1} \cdot \sqrt{x + 1}}\right)} - \log \left(e^{\sqrt{x} \cdot \sqrt{x}}\right)}{\sqrt{x + 1} + \sqrt{x}}\]
  7. Applied diff-log31.1

    \[\leadsto \frac{\color{blue}{\log \left(\frac{e^{\sqrt{x + 1} \cdot \sqrt{x + 1}}}{e^{\sqrt{x} \cdot \sqrt{x}}}\right)}}{\sqrt{x + 1} + \sqrt{x}}\]
  8. Simplified29.4

    \[\leadsto \frac{\log \color{blue}{\left(e^{\left(1 + x\right) - x}\right)}}{\sqrt{x + 1} + \sqrt{x}}\]
  9. Using strategy rm
  10. Applied associate--l+0.2

    \[\leadsto \frac{\log \left(e^{\color{blue}{1 + \left(x - x\right)}}\right)}{\sqrt{x + 1} + \sqrt{x}}\]
  11. Using strategy rm
  12. Applied add-sqr-sqrt0.3

    \[\leadsto \frac{\log \left(e^{1 + \left(x - x\right)}\right)}{\color{blue}{\sqrt{\sqrt{x + 1} + \sqrt{x}} \cdot \sqrt{\sqrt{x + 1} + \sqrt{x}}}}\]
  13. Applied add-cube-cbrt0.3

    \[\leadsto \frac{\log \left(e^{\color{blue}{\left(\sqrt[3]{1 + \left(x - x\right)} \cdot \sqrt[3]{1 + \left(x - x\right)}\right) \cdot \sqrt[3]{1 + \left(x - x\right)}}}\right)}{\sqrt{\sqrt{x + 1} + \sqrt{x}} \cdot \sqrt{\sqrt{x + 1} + \sqrt{x}}}\]
  14. Applied exp-prod0.3

    \[\leadsto \frac{\log \color{blue}{\left({\left(e^{\sqrt[3]{1 + \left(x - x\right)} \cdot \sqrt[3]{1 + \left(x - x\right)}}\right)}^{\left(\sqrt[3]{1 + \left(x - x\right)}\right)}\right)}}{\sqrt{\sqrt{x + 1} + \sqrt{x}} \cdot \sqrt{\sqrt{x + 1} + \sqrt{x}}}\]
  15. Applied log-pow0.3

    \[\leadsto \frac{\color{blue}{\sqrt[3]{1 + \left(x - x\right)} \cdot \log \left(e^{\sqrt[3]{1 + \left(x - x\right)} \cdot \sqrt[3]{1 + \left(x - x\right)}}\right)}}{\sqrt{\sqrt{x + 1} + \sqrt{x}} \cdot \sqrt{\sqrt{x + 1} + \sqrt{x}}}\]
  16. Applied times-frac0.4

    \[\leadsto \color{blue}{\frac{\sqrt[3]{1 + \left(x - x\right)}}{\sqrt{\sqrt{x + 1} + \sqrt{x}}} \cdot \frac{\log \left(e^{\sqrt[3]{1 + \left(x - x\right)} \cdot \sqrt[3]{1 + \left(x - x\right)}}\right)}{\sqrt{\sqrt{x + 1} + \sqrt{x}}}}\]
  17. Simplified0.3

    \[\leadsto \color{blue}{{\left(\sqrt{x + 1} + \sqrt{x}\right)}^{\left(-\frac{1}{2}\right)}} \cdot \frac{\log \left(e^{\sqrt[3]{1 + \left(x - x\right)} \cdot \sqrt[3]{1 + \left(x - x\right)}}\right)}{\sqrt{\sqrt{x + 1} + \sqrt{x}}}\]
  18. Simplified0.3

    \[\leadsto {\left(\sqrt{x + 1} + \sqrt{x}\right)}^{\left(-\frac{1}{2}\right)} \cdot \color{blue}{{\left(\sqrt{x + 1} + \sqrt{x}\right)}^{\left(-\frac{1}{2}\right)}}\]
  19. Final simplification0.3

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

Runtime

Time bar (total: 4.2m)Debug logProfile

herbie shell --seed 2018214 +o rules:numerics
(FPCore (x)
  :name "2sqrt (example 3.1)"

  :herbie-target
  (/ 1 (+ (sqrt (+ x 1)) (sqrt x)))

  (- (sqrt (+ x 1)) (sqrt x)))