Compute the complementary error function 1 - erf (X).
∞
2 /
erfc (x) = ----- |exp (-t²) dt
√π /
x
Accuracy: The result is a tight enclosure.
erfc (infsup (1)) ⇒ ans ⊂ [0.15729, 0.1573]
See also: @infsup/erf.
Package: interval