Explore related knowledge and questions →

Question 6401: Rational Division Eligibility and Multiplication Back

On this page
  1. Original question and givens
  2. Definition and scope
  3. Step-by-step derivation
  4. Reverse checks
  5. Result
  6. This question review and source binding

Return to catalogue page 33

← Question derivation index · Original question batch

R0011-06401 · q-20261009-advance-20261013-r03-rational-number-0051

Original question and givens

Exact rational representations have nonzero denominators; a=5/-2, b=0/-3. Negative input denominators are allowed. Give (is b nonzero?, a/b or undefined, (a/b)b or undefined). Use exact reduced fractions with positive denominators, retaining /1 for integers.

  • G001 — Exact rational representations have nonzero denominators; a=5/-2, b=0/-3. Negative input denominators are allowed. Give (is b nonzero?, a/b or undefined, (a/b)b or undefined). Use exact reduced fractions with positive denominators, retaining /1 for integers.

Definition and scope

Use the original question domain, assumptions and cited MKO definitions. This item has second-context mathematical and bilingual review, with the model, answer and every arithmetic step independently recomputed from the original parameters; the source question remains a candidate.

Step-by-step derivation

S001 · implies

Before

raw a=[5, -2];raw b=[0, -3]

After

a=-5/2;b=0/1

Conditions: none

Original denominators need only be nonzero;negative denominators are valid.Normalize to reduced positive-denominator fractions for exact arithmetic while retaining the original representations and sources.

Step identifiers and dependencies

Rule: nonzero_signed_rational_representation · Uses: G001

S002 · implies

Before

divisor value b=0/1

After

quotient and reverse product are undefined

Conditions: none

Division is invalid when the divisor's value is0,even if its original denominator is negative;do not invent a quotient and certify it by multiplying back.

Step identifiers and dependencies

Rule: rational_zero_divisor_guard · Uses: G001, S001

Reverse checks

  • S002 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
  • S001 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.

Result

(No, undefined, undefined)

The full substitutions and premise checks give the original answer; source identity,format and status are unchanged.

This question review and source binding

Review date: 2026-10-26

Original questions, answers, step expressions, numeric ASTs and historical records are retained. Source candidate labels remain historical and are not overwritten as formal proof.

Source hashes and review receipts
  • input commit: 0f7be61e2c22317a4075561dc822c87d881a50db
  • original question SHA-256: 5aa64edef2fa3feee6a059543a1b6947a5b9f9c295dbaa0b4df76e5d9f6b030d
  • candidate record SHA-256: 7b48f8f064cf4100255440cd2a44097ef7956b141a05156468e6f1899101785f
  • semantic review receipt SHA-256: b9bbc1c947f477a9c4bb5a579368ac5265f2da4572ce612c30f3633ecaf4ae80
  • question-first witness SHA-256: 93f720df3ab3af13a792a3e6b443728e3c2a56276df839911f36569333236c55
  • Lean: NOT_RUN · human review: NOT_PERFORMED
Same-source full JSON