Reference · Signed rationals
rainbow.math.rational.signed.square-monotone
B6b of the limit-reciprocal arc: squaring is monotone on nonnegatives. signed/square-monotone : 0 <= a -> a <= b -> a*a <= b*b Two applications of multiply-right-monotone: a*a <= b*a (multiply a<=b by a>=0) and a*b <= b*b (multiply a<=b by b>=0, where 0<=b from 0<=a<=b); align b*a ~ a*b by commutativity and chain by transitivity. Feeds the assembly's positivity derivation (with magnitude-monotone: |L|/2 <= |s n| -> (|L|/2)^2 <= (s n)^2 -> mag positive). Axiom-free; additive; does not touch the LP checker.
signed/square-monotone
signed/square-monotone : (a b : ℚ) (ha : 0 ≤ a) (hab : a ≤ b) → a · a ≤ b · b
0 = signed/zero· = signed/multiplyℚ = signed/SignedRational≤ = signed/at-most