\[\sqrt{\frac{-2.839573235346269 \cdot 10^{-37}}{\left(a \cdot b\right) \cdot \left|a\right|}}\]
Test:
(sqrt (/ -2.839573235346269e-37 (* (* a b) (fabs a))))
Bits:
128 bits
Bits error versus a
Bits error versus b
Time: 5.2 s
Input Error: 9.9
Output Error: 8.9
Log: ⚲
Profile: 🕒
\(\sqrt{\frac{-2.839573235346269 \cdot 10^{-37}}{b \cdot \left(\left|a\right| \cdot a\right)}}\)
  1. Started with
    \[\sqrt{\frac{-2.839573235346269 \cdot 10^{-37}}{\left(a \cdot b\right) \cdot \left|a\right|}}\]
    9.9
  2. Applied taylor to get
    \[\sqrt{\frac{-2.839573235346269 \cdot 10^{-37}}{\left(a \cdot b\right) \cdot \left|a\right|}} \leadsto \sqrt{\frac{-2.839573235346269 \cdot 10^{-37}}{b \cdot \left(\left|a\right| \cdot a\right)}}\]
    8.9
  3. Taylor expanded around 0 to get
    \[\sqrt{\color{red}{\frac{-2.839573235346269 \cdot 10^{-37}}{b \cdot \left(\left|a\right| \cdot a\right)}}} \leadsto \sqrt{\color{blue}{\frac{-2.839573235346269 \cdot 10^{-37}}{b \cdot \left(\left|a\right| \cdot a\right)}}}\]
    8.9

Original test:


(lambda ((a default) (b default))
  #:name "(sqrt (/ -2.839573235346269e-37 (* (* a b) (fabs a))))"
  (sqrt (/ -2.839573235346269e-37 (* (* a b) (fabs a)))))