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R0006-03983 · q-20261007-advance-20261009-r03-function-limit-0083
The original quotient (x²−(-5)²)/(x−(-5)) has punctured real domain x≠a. Evaluate it at the permitted x=-9. Use reduced positive-denominator fractions, retaining /1 for integers.
G001 — The original quotient (x²−(-5)²)/(x−(-5)) has punctured real domain x≠a. Evaluate it at the permitted x=-9. Use reduced positive-denominator fractions, retaining /1 for integers.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.
Before
declared real model with an excluded center for limit data
After
point value,legal off-center evaluation and limit are distinct
Conditions: none
A punctured limit does not read the center value,and evaluation at one legal point is not a limit.These declared affine or factorizable models do not represent arbitrary functions.
Rule: punctured_limit_scope · Uses: G001
Before
x squared := square(-9)
After
x squared = 81
Conditions: none
Square the entire specified legal input.
Rule: exact_rational_arithmetic · Uses: G001, S001
Before
center squared := square(-5)
After
center squared = 25
Conditions: none
Square the entire center,including any negative sign.
Rule: exact_rational_arithmetic · Uses: G001, S002
Before
difference of squares := sub(81, 25)
After
difference of squares = 56
Conditions: none
The numerator is x²−a².
Rule: exact_rational_arithmetic · Uses: G001, S003
Before
nonzero punctured denominator := sub(-9, -5)
After
nonzero punctured denominator = -4
Conditions: none
Check x−a≠0 before division.
Rule: exact_rational_arithmetic · Uses: G001, S004
Before
legal quotient value := div(56, -4)
After
legal quotient value = -14
Conditions: none
Divide exactly only at the legal point of the original quotient;do not fill its center value.
Rule: exact_rational_arithmetic · Uses: G001, S005
Before
x=-9≠a=-5
After
(x²−a²)/(x−a)=x+a=-14
Conditions: none
Factorization audits the result;the cancellation identity retains x≠a and does not define the original quotient at a.
Rule: legal_quotient_factor_audit · Uses: G001, S006
S007 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.S006 · premise_and_result_audit — Recompute legal quotient value with exact rational arithmetic, not rounded decimals.S005 · premise_and_result_audit — Recompute nonzero punctured denominator with exact rational arithmetic, not rounded decimals.S004 · premise_and_result_audit — Recompute difference of squares with exact rational arithmetic, not rounded decimals.S003 · premise_and_result_audit — Recompute center squared with exact rational arithmetic, not rounded decimals.S002 · premise_and_result_audit — Recompute x squared with exact rational arithmetic, not rounded decimals.S001 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.-14/1
The full substitutions and premise checks give the original answer; source identity,format and status are unchanged.
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.
input commit: 0f7be61e2c22317a4075561dc822c87d881a50dboriginal question SHA-256: 25aad6f7801eb53cb0aa287b6bc34699fa7983430598f9b422e7382c80122ecbcandidate record SHA-256: f2c2814fb8547a4485414dbfa7324a5c67d63c194c34383b050e083d5a8acebcsemantic review receipt SHA-256: 568eefd71709ac3dc16a0d5b3b4ad3e83376a8ef300c9e5493eee0721500b29dquestion-first witness SHA-256: d964b91bedb9d4918bbc055f567762a09f5a58af6c876268e719d5100332d855Lean: NOT_RUN · human review: NOT_PERFORMED