\[\frac{x}{{x}^2 + 1}\]
Test:
x / (x^2 + 1)
Bits:
128 bits
Bits error versus x
Time: 4.4 s
Input Error: 15.1
Output Error: 0.0
Log: ⚲
Profile: 🕒
\(\begin{cases} \frac{1}{{x}^{5}} - \left(\frac{1}{{x}^3} - \frac{1}{x}\right) & \text{when } x \le -1.5553509784044383 \cdot 10^{+18} \\ \frac{x}{{x}^2 + 1} & \text{when } x \le 40559.850189135206 \\ \frac{1}{{x}^{5}} - \left(\frac{1}{{x}^3} - \frac{1}{x}\right) & \text{otherwise} \end{cases}\)

    if x < -1.5553509784044383e+18 or 40559.850189135206 < x

    1. Started with
      \[\frac{x}{{x}^2 + 1}\]
      31.2
    2. Applied taylor to get
      \[\frac{x}{{x}^2 + 1} \leadsto \left(\frac{1}{{x}^{5}} + \frac{1}{x}\right) - \frac{1}{{x}^{3}}\]
      0.0
    3. Taylor expanded around inf to get
      \[\color{red}{\left(\frac{1}{{x}^{5}} + \frac{1}{x}\right) - \frac{1}{{x}^{3}}} \leadsto \color{blue}{\left(\frac{1}{{x}^{5}} + \frac{1}{x}\right) - \frac{1}{{x}^{3}}}\]
      0.0
    4. Applied simplify to get
      \[\color{red}{\left(\frac{1}{{x}^{5}} + \frac{1}{x}\right) - \frac{1}{{x}^{3}}} \leadsto \color{blue}{\frac{1}{{x}^{5}} - \left(\frac{1}{{x}^3} - \frac{1}{x}\right)}\]
      0.0

    if -1.5553509784044383e+18 < x < 40559.850189135206

    1. Started with
      \[\frac{x}{{x}^2 + 1}\]
      0.0
  1. Removed slow pow expressions

Original test:


(lambda ((x default))
  #:name "x / (x^2 + 1)"
  (/ x (+ (sqr x) 1))
  #:target
  (/ 1 (+ x (/ 1 x))))