Reference · Signed rationals
rainbow.math.rational.signed.close-radius-monotone
Band weakening: a closeness band only widens with its radius. analysis/close-radius-monotone : close L r x -> r <= r' -> close L r' x. From close = (L-r<=x) AND (x<=L+r): L-r'<=L-r<=x (negate-reverses-order + add-monotone) and x<=L+r<=L+r' (add-monotone). Axiom-free; additive. A generally useful analysis lemma (and the >=-relaxation the limit-product assembly wants).
analysis/close-radius-monotone
analysis/close-radius-monotone : (L r x r2 : ℚ) (hc : analysis/close L r x) (hr : r ≤ r2) → analysis/close L r2 x
ℚ = signed/SignedRational≤ = signed/at-most