Explore related knowledge and questions →

Question 32300: Affine δ Witness with Strict Punctured Interior

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 162

← Question derivation index · Original question batch

R0063-32300 · q-20261007-advance-20261008-r02-function-limit-0075

Original question and givens

For arbitrary real A,L, define f(x)=L+(24)(x−A) for x≠A on R∖{A}. With ε=1/1>0 and δ=2/24>0, does 0<|x−A|<δ guarantee |f(x)−L|<ε?

  • G001 — For arbitrary real A,L, define f(x)=L+(24)(x−A) for x≠A on R∖{A}. With ε=1/1>0 and δ=2/24>0, does 0<|x−A|<δ guarantee |f(x)−L|<ε?

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

source roles = [qf-function-limit-affine-delta, affine_delta_validity, punctured_reals, []]

After

derived = [[nonstrict_budget_YesNo_STRING]]

Conditions: none

BASE sources do not acquire a generic legacy operation/domain or unknown-metadata ban.Retain metadata WITHOUT using it as an answer oracle.PULSE/legacy enforce their exact source keys,operation/domain.Do not impose universal tuples,/1 or input bounds.

Step identifiers and dependencies

Rule: R63_SOURCE_bank_keys_operation_domain_output_roles_metadata_not_oracle · Uses: G001

S002 · calculation

Before

Delta ORIGINAL absolute slope times delta numerator := mul(24, 2)

After

Delta ORIGINAL absolute slope times delta numerator = 48

Conditions: none

Use ORIGINAL operands and order for exact integer/rational arithmetic.Raw bounds are bank-specific;derived values do not inherit SAFE or foreign small caps.No floating approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S001

S003 · calculation

Before

Delta ORIGINAL left cross product times epsilon denominator := mul(48, 1)

After

Delta ORIGINAL left cross product times epsilon denominator = 48

Conditions: none

Use ORIGINAL operands and order for exact integer/rational arithmetic.Raw bounds are bank-specific;derived values do not inherit SAFE or foreign small caps.No floating approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S002

S004 · calculation

Before

Delta ORIGINAL epsilon numerator times delta denominator := mul(1, 24)

After

Delta ORIGINAL epsilon numerator times delta denominator = 24

Conditions: none

Use ORIGINAL operands and order for exact integer/rational arithmetic.Raw bounds are bank-specific;derived values do not inherit SAFE or foreign small caps.No floating approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S003

S005 · implies

Before

source roles = [24, 1, 1, 2, 24]

After

derived = [1/1, 1/12, 48, 24, No]

Conditions: none

FIRST validate ALL FOUR positive raw fraction components,EVEN at m0.Because the input distance is STRICTLY below δ,the budget criterion is|m|δ≤ε,NOT<.Equality is legal;m0 gives error0.The target is L,not undefined f(A);A/L are arbitrary fixed reals,not invented parameters.

Step identifiers and dependencies

Rule: Limit_DELTA_ALL_positive_components_NONSTRICT_budget_STRICT_punctured_input · Uses: G001, S004

S006 · calculation

Before

Delta counterexample ORIGINAL epsilon over nonzero absolute slope := div(1, 24)

After

Delta counterexample ORIGINAL epsilon over nonzero absolute slope = 1/24

Conditions: none

Use ORIGINAL operands and order for exact integer/rational arithmetic.Raw bounds are bank-specific;derived values do not inherit SAFE or foreign small caps.No floating approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S005

S007 · calculation

Before

Delta counterexample ORIGINAL delta plus threshold := sum(1/12, 1/24)

After

Delta counterexample ORIGINAL delta plus threshold = 1/8

Conditions: none

Use ORIGINAL operands and order for exact integer/rational arithmetic.Raw bounds are bank-specific;derived values do not inherit SAFE or foreign small caps.No floating approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S006

S008 · calculation

Before

Delta counterexample ORIGINAL midpoint distance := div(1/8, 2)

After

Delta counterexample ORIGINAL midpoint distance = 1/16

Conditions: none

Use ORIGINAL operands and order for exact integer/rational arithmetic.Raw bounds are bank-specific;derived values do not inherit SAFE or foreign small caps.No floating approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S007

S009 · calculation

Before

Delta counterexample ORIGINAL absolute slope times distance := mul(24, 1/16)

After

Delta counterexample ORIGINAL absolute slope times distance = 3/2

Conditions: none

Use ORIGINAL operands and order for exact integer/rational arithmetic.Raw bounds are bank-specific;derived values do not inherit SAFE or foreign small caps.No floating approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S008

S010 · calculation

Before

Delta counterexample ORIGINAL delta minus distance := sub(1/12, 1/16)

After

Delta counterexample ORIGINAL delta minus distance = 1/48

Conditions: none

Use ORIGINAL operands and order for exact integer/rational arithmetic.Raw bounds are bank-specific;derived values do not inherit SAFE or foreign small caps.No floating approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S009

S011 · calculation

Before

Delta counterexample ORIGINAL error minus epsilon := sub(3/2, 1)

After

Delta counterexample ORIGINAL error minus epsilon = 1/2

Conditions: none

Use ORIGINAL operands and order for exact integer/rational arithmetic.Raw bounds are bank-specific;derived values do not inherit SAFE or foreign small caps.No floating approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S010

S012 · implies

Before

source roles = [24, 1/1, 1/12]

After

derived = [1/24, 1/16, 3/2, 1/48, 1/2, choose x = A+r]

Conditions: none

When|m|δ>ε and m≠0,r=(δ+ε/|m|)/2 lies STRICTLY between0 andδ while|m|r>ε.Choosing x=A+r is an explicit counterexample,not a sampling extrapolation or division by0.

Step identifiers and dependencies

Rule: Limit_DELTA_NO_explicit_inside_distance_ERROR_above_epsilon · Uses: G001, S011

Reverse checks

  • S012 · premise_and_result_audit — Reverse-check ORIGINAL inputs,types,domain and premises;the conclusion need not uniquely recover its premises.Keep source-bound candidates,independent review,formal proof and publication separate.
  • S011 · premise_and_result_audit — Recompute Delta counterexample ORIGINAL error minus epsilon with exact rational arithmetic, not rounded decimals.
  • S010 · premise_and_result_audit — Recompute Delta counterexample ORIGINAL delta minus distance with exact rational arithmetic, not rounded decimals.
  • S009 · premise_and_result_audit — Recompute Delta counterexample ORIGINAL absolute slope times distance with exact rational arithmetic, not rounded decimals.
  • S008 · premise_and_result_audit — Recompute Delta counterexample ORIGINAL midpoint distance with exact rational arithmetic, not rounded decimals.
  • S007 · premise_and_result_audit — Recompute Delta counterexample ORIGINAL delta plus threshold with exact rational arithmetic, not rounded decimals.
  • S006 · premise_and_result_audit — Recompute Delta counterexample ORIGINAL epsilon over nonzero absolute slope with exact rational arithmetic, not rounded decimals.
  • S005 · premise_and_result_audit — Reverse-check ORIGINAL inputs,types,domain and premises;the conclusion need not uniquely recover its premises.Keep source-bound candidates,independent review,formal proof and publication separate.
  • S004 · premise_and_result_audit — Recompute Delta ORIGINAL epsilon numerator times delta denominator with exact rational arithmetic, not rounded decimals.
  • S003 · premise_and_result_audit — Recompute Delta ORIGINAL left cross product times epsilon denominator with exact rational arithmetic, not rounded decimals.
  • S002 · premise_and_result_audit — Recompute Delta ORIGINAL absolute slope times delta numerator with exact rational arithmetic, not rounded decimals.
  • S001 · premise_and_result_audit — Reverse-check ORIGINAL inputs,types,domain and premises;the conclusion need not uniquely recover its premises.Keep source-bound candidates,independent review,formal proof and publication separate.

Result

No

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: 49ad1565e0990d42fb3f69f88add2f45103fa5bdff83410930295dee3a624764
  • candidate record SHA-256: f45a11bb02060d8e8357d6bd2187a7936b7792c2db08159daba5bc4a9dd305d2
  • semantic review receipt SHA-256: acf03b776f4855e3869810bcbecf1116e3a2b11dfb1e2a5dfbcf8135ad24a7d0
  • question-first witness SHA-256: eadbbac3220988b52754f32450fb536d627217306d1ce28a49134f56c21bfa88
  • Lean: NOT_RUN · human review: NOT_PERFORMED
Same-source full JSON