Reference · Signed rationals
rainbow.math.rational.signed.product-radius-nonneg
First sub-proof of the limit-product modulus assembly: the radius base V = (1 + |L|) + |M| is nonnegative (indeed a sum of nonnegatives), so signed/from-nnrat-magnitude applies to it. Axiom-free; additive. analysis/product-radius-nonneg : forall L M, signed/nonnegative (signed-add (signed-add one (absolute L)) (absolute M))
analysis/product-radius-nonneg
analysis/product-radius-nonneg : (L M : ℚ) → signed/nonnegative (1 + signed/absolute L + signed/absolute M)
+ = signed/add1 = signed/oneℚ = signed/SignedRational