\[\cos \left(x + \varepsilon\right) - \cos x\]
Test:
NMSE problem 3.3.5
Bits:
128 bits
Bits error versus x
Bits error versus eps
Time: 25.6 s
Input Error: 18.7
Output Error: 0.5
Log:
Profile: 🕒
\(\begin{cases} \frac{\frac{{\left({\left(\cos \varepsilon \cdot \cos x\right)}^3 - {\left(\sin x \cdot \sin \varepsilon\right)}^3\right)}^2}{{\left({\left(\cos x \cdot \cos \varepsilon\right)}^2 + \left({\left(\sin x \cdot \sin \varepsilon\right)}^2 + \left(\cos x \cdot \cos \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right)\right)\right)}^2} - {\left(\cos x\right)}^2}{(\left(\cos \varepsilon\right) * \left(\cos x\right) + \left(\cos x\right))_* - \sin \varepsilon \cdot \sin x} & \text{when } \varepsilon \le -0.0035937247f0 \\ \frac{(\left(\sin x \cdot \sin x\right) * \left(\varepsilon \cdot \varepsilon\right) + \left(\left(\sin x \cdot \left(\varepsilon \cdot \frac{4}{3}\right)\right) \cdot \left(\cos x \cdot \left(\varepsilon \cdot \varepsilon\right)\right)\right))_* - (\left(\cos x\right) * \varepsilon + \left(\sin x \cdot 2\right))_* \cdot \left(\varepsilon \cdot \cos x\right)}{(\left(\cos \varepsilon\right) * \left(\cos x\right) + \left(\cos x\right))_* - \sin \varepsilon \cdot \sin x} & \text{when } \varepsilon \le 0.3662591f0 \\ \frac{\frac{{\left({\left(\cos \varepsilon \cdot \cos x\right)}^3 - {\left(\sin x \cdot \sin \varepsilon\right)}^3\right)}^2}{{\left({\left(\cos x \cdot \cos \varepsilon\right)}^2 + \left({\left(\sin x \cdot \sin \varepsilon\right)}^2 + \left(\cos x \cdot \cos \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right)\right)\right)}^2} - {\left(\cos x\right)}^2}{(\left(\cos \varepsilon\right) * \left(\cos x\right) + \left(\cos x\right))_* - \sin \varepsilon \cdot \sin x} & \text{otherwise} \end{cases}\)

    if eps < -0.0035937247f0 or 0.3662591f0 < eps

    1. Started with
      \[\cos \left(x + \varepsilon\right) - \cos x\]
      14.7
    2. Using strategy rm
      14.7
    3. Applied cos-sum to get
      \[\color{red}{\cos \left(x + \varepsilon\right)} - \cos x \leadsto \color{blue}{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right)} - \cos x\]
      0.8
    4. Using strategy rm
      0.8
    5. Applied flip-- to get
      \[\color{red}{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right) - \cos x} \leadsto \color{blue}{\frac{{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right)}^2 - {\left(\cos x\right)}^2}{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right) + \cos x}}\]
      0.8
    6. Applied simplify to get
      \[\frac{{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right)}^2 - {\left(\cos x\right)}^2}{\color{red}{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right) + \cos x}} \leadsto \frac{{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right)}^2 - {\left(\cos x\right)}^2}{\color{blue}{(\left(\cos \varepsilon\right) * \left(\cos x\right) + \left(\cos x\right))_* - \sin \varepsilon \cdot \sin x}}\]
      0.9
    7. Using strategy rm
      0.9
    8. Applied flip3-- to get
      \[\frac{{\color{red}{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right)}}^2 - {\left(\cos x\right)}^2}{(\left(\cos \varepsilon\right) * \left(\cos x\right) + \left(\cos x\right))_* - \sin \varepsilon \cdot \sin x} \leadsto \frac{{\color{blue}{\left(\frac{{\left(\cos x \cdot \cos \varepsilon\right)}^{3} - {\left(\sin x \cdot \sin \varepsilon\right)}^{3}}{{\left(\cos x \cdot \cos \varepsilon\right)}^2 + \left({\left(\sin x \cdot \sin \varepsilon\right)}^2 + \left(\cos x \cdot \cos \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right)\right)}\right)}}^2 - {\left(\cos x\right)}^2}{(\left(\cos \varepsilon\right) * \left(\cos x\right) + \left(\cos x\right))_* - \sin \varepsilon \cdot \sin x}\]
      1.8
    9. Applied square-div to get
      \[\frac{\color{red}{{\left(\frac{{\left(\cos x \cdot \cos \varepsilon\right)}^{3} - {\left(\sin x \cdot \sin \varepsilon\right)}^{3}}{{\left(\cos x \cdot \cos \varepsilon\right)}^2 + \left({\left(\sin x \cdot \sin \varepsilon\right)}^2 + \left(\cos x \cdot \cos \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right)\right)}\right)}^2} - {\left(\cos x\right)}^2}{(\left(\cos \varepsilon\right) * \left(\cos x\right) + \left(\cos x\right))_* - \sin \varepsilon \cdot \sin x} \leadsto \frac{\color{blue}{\frac{{\left({\left(\cos x \cdot \cos \varepsilon\right)}^{3} - {\left(\sin x \cdot \sin \varepsilon\right)}^{3}\right)}^2}{{\left({\left(\cos x \cdot \cos \varepsilon\right)}^2 + \left({\left(\sin x \cdot \sin \varepsilon\right)}^2 + \left(\cos x \cdot \cos \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right)\right)\right)}^2}} - {\left(\cos x\right)}^2}{(\left(\cos \varepsilon\right) * \left(\cos x\right) + \left(\cos x\right))_* - \sin \varepsilon \cdot \sin x}\]
      1.8
    10. Applied simplify to get
      \[\frac{\frac{\color{red}{{\left({\left(\cos x \cdot \cos \varepsilon\right)}^{3} - {\left(\sin x \cdot \sin \varepsilon\right)}^{3}\right)}^2}}{{\left({\left(\cos x \cdot \cos \varepsilon\right)}^2 + \left({\left(\sin x \cdot \sin \varepsilon\right)}^2 + \left(\cos x \cdot \cos \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right)\right)\right)}^2} - {\left(\cos x\right)}^2}{(\left(\cos \varepsilon\right) * \left(\cos x\right) + \left(\cos x\right))_* - \sin \varepsilon \cdot \sin x} \leadsto \frac{\frac{\color{blue}{{\left({\left(\cos \varepsilon \cdot \cos x\right)}^3 - {\left(\sin x \cdot \sin \varepsilon\right)}^3\right)}^2}}{{\left({\left(\cos x \cdot \cos \varepsilon\right)}^2 + \left({\left(\sin x \cdot \sin \varepsilon\right)}^2 + \left(\cos x \cdot \cos \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right)\right)\right)}^2} - {\left(\cos x\right)}^2}{(\left(\cos \varepsilon\right) * \left(\cos x\right) + \left(\cos x\right))_* - \sin \varepsilon \cdot \sin x}\]
      0.9

    if -0.0035937247f0 < eps < 0.3662591f0

    1. Started with
      \[\cos \left(x + \varepsilon\right) - \cos x\]
      22.9
    2. Using strategy rm
      22.9
    3. Applied cos-sum to get
      \[\color{red}{\cos \left(x + \varepsilon\right)} - \cos x \leadsto \color{blue}{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right)} - \cos x\]
      18.5
    4. Using strategy rm
      18.5
    5. Applied flip-- to get
      \[\color{red}{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right) - \cos x} \leadsto \color{blue}{\frac{{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right)}^2 - {\left(\cos x\right)}^2}{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right) + \cos x}}\]
      18.5
    6. Applied simplify to get
      \[\frac{{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right)}^2 - {\left(\cos x\right)}^2}{\color{red}{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right) + \cos x}} \leadsto \frac{{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right)}^2 - {\left(\cos x\right)}^2}{\color{blue}{(\left(\cos \varepsilon\right) * \left(\cos x\right) + \left(\cos x\right))_* - \sin \varepsilon \cdot \sin x}}\]
      18.5
    7. Using strategy rm
      18.5
    8. Applied add-cube-cbrt to get
      \[\frac{\color{red}{{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right)}^2 - {\left(\cos x\right)}^2}}{(\left(\cos \varepsilon\right) * \left(\cos x\right) + \left(\cos x\right))_* - \sin \varepsilon \cdot \sin x} \leadsto \frac{\color{blue}{{\left(\sqrt[3]{{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right)}^2 - {\left(\cos x\right)}^2}\right)}^3}}{(\left(\cos \varepsilon\right) * \left(\cos x\right) + \left(\cos x\right))_* - \sin \varepsilon \cdot \sin x}\]
      18.5
    9. Applied taylor to get
      \[\frac{{\left(\sqrt[3]{{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right)}^2 - {\left(\cos x\right)}^2}\right)}^3}{(\left(\cos \varepsilon\right) * \left(\cos x\right) + \left(\cos x\right))_* - \sin \varepsilon \cdot \sin x} \leadsto \frac{\left(\frac{4}{3} \cdot \left({\varepsilon}^{3} \cdot \left(\sin x \cdot \cos x\right)\right) + {\varepsilon}^2 \cdot {\left(\sin x\right)}^2\right) - \left(2 \cdot \left(\varepsilon \cdot \left(\sin x \cdot \cos x\right)\right) + {\varepsilon}^2 \cdot {\left(\cos x\right)}^2\right)}{(\left(\cos \varepsilon\right) * \left(\cos x\right) + \left(\cos x\right))_* - \sin \varepsilon \cdot \sin x}\]
      0.2
    10. Taylor expanded around 0 to get
      \[\frac{\color{red}{\left(\frac{4}{3} \cdot \left({\varepsilon}^{3} \cdot \left(\sin x \cdot \cos x\right)\right) + {\varepsilon}^2 \cdot {\left(\sin x\right)}^2\right) - \left(2 \cdot \left(\varepsilon \cdot \left(\sin x \cdot \cos x\right)\right) + {\varepsilon}^2 \cdot {\left(\cos x\right)}^2\right)}}{(\left(\cos \varepsilon\right) * \left(\cos x\right) + \left(\cos x\right))_* - \sin \varepsilon \cdot \sin x} \leadsto \frac{\color{blue}{\left(\frac{4}{3} \cdot \left({\varepsilon}^{3} \cdot \left(\sin x \cdot \cos x\right)\right) + {\varepsilon}^2 \cdot {\left(\sin x\right)}^2\right) - \left(2 \cdot \left(\varepsilon \cdot \left(\sin x \cdot \cos x\right)\right) + {\varepsilon}^2 \cdot {\left(\cos x\right)}^2\right)}}{(\left(\cos \varepsilon\right) * \left(\cos x\right) + \left(\cos x\right))_* - \sin \varepsilon \cdot \sin x}\]
      0.2
    11. Applied simplify to get
      \[\frac{\left(\frac{4}{3} \cdot \left({\varepsilon}^{3} \cdot \left(\sin x \cdot \cos x\right)\right) + {\varepsilon}^2 \cdot {\left(\sin x\right)}^2\right) - \left(2 \cdot \left(\varepsilon \cdot \left(\sin x \cdot \cos x\right)\right) + {\varepsilon}^2 \cdot {\left(\cos x\right)}^2\right)}{(\left(\cos \varepsilon\right) * \left(\cos x\right) + \left(\cos x\right))_* - \sin \varepsilon \cdot \sin x} \leadsto \frac{(\left(\sin x \cdot \sin x\right) * \left(\varepsilon \cdot \varepsilon\right) + \left(\left(\left(\frac{4}{3} \cdot \varepsilon\right) \cdot \left(\varepsilon \cdot \varepsilon\right)\right) \cdot \left(\cos x \cdot \sin x\right)\right))_* - \cos x \cdot \left(\left(\varepsilon \cdot \varepsilon\right) \cdot \cos x + \left(2 \cdot \varepsilon\right) \cdot \sin x\right)}{(\left(\cos \varepsilon\right) * \left(\cos x\right) + \left(\cos x\right))_* - \sin \varepsilon \cdot \sin x}\]
      0.2

    12. Applied final simplification
    13. Applied simplify to get
      \[\color{red}{\frac{(\left(\sin x \cdot \sin x\right) * \left(\varepsilon \cdot \varepsilon\right) + \left(\left(\left(\frac{4}{3} \cdot \varepsilon\right) \cdot \left(\varepsilon \cdot \varepsilon\right)\right) \cdot \left(\cos x \cdot \sin x\right)\right))_* - \cos x \cdot \left(\left(\varepsilon \cdot \varepsilon\right) \cdot \cos x + \left(2 \cdot \varepsilon\right) \cdot \sin x\right)}{(\left(\cos \varepsilon\right) * \left(\cos x\right) + \left(\cos x\right))_* - \sin \varepsilon \cdot \sin x}} \leadsto \color{blue}{\frac{(\left(\sin x \cdot \sin x\right) * \left(\varepsilon \cdot \varepsilon\right) + \left(\left(\sin x \cdot \left(\varepsilon \cdot \frac{4}{3}\right)\right) \cdot \left(\cos x \cdot \left(\varepsilon \cdot \varepsilon\right)\right)\right))_* - (\left(\cos x\right) * \varepsilon + \left(\sin x \cdot 2\right))_* \cdot \left(\varepsilon \cdot \cos x\right)}{(\left(\cos \varepsilon\right) * \left(\cos x\right) + \left(\cos x\right))_* - \sin \varepsilon \cdot \sin x}}\]
      0.2

  1. Removed slow pow expressions

Original test:


(lambda ((x default) (eps default))
  #:name "NMSE problem 3.3.5"
  (- (cos (+ x eps)) (cos x)))