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Question 27999: Squared Distance with One Regular Linear Constraint Has an Exact Solution

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

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← Question derivation index · Original question batch

R0054-27999 · q-20261015-pulse-20261119-r04-0074

Original question and givens

Minimize squared Euclidean distance to center=[3, 2] subject to normal a=[1, 24], a dot x=26; require a nonzero normal. Give (center, constraint_gradient, constraint_rhs, normal_displacement_coefficient, solution_point, multiplier, objective_gradient, feasible, stationary, specified_problem_scope).

  • G001 — Minimize squared Euclidean distance to center=[3, 2] subject to normal a=[1, 24], a dot x=26; require a nonzero normal. Give (center, constraint_gradient, constraint_rhs, normal_displacement_coefficient, solution_point, multiplier, objective_gradient, feasible, stationary, specified_problem_scope).

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 = [lagrange-single-linear-constraint]

After

derived = [[center, constraint_gradient, constraint_rhs, normal_displacement_coefficient, solution_point, multiplier, objective_gradient, feasible, stationary, specified_problem_scope]]

Conditions: none

List the complete operation/mode field order without JavaScript or answer-shape inference;Boolean,string,null and an unclaimed result remain distinct.

Step identifiers and dependencies

Rule: source_ordered_fields_without_JS · Uses: G001

S002 · calculation

Before

Lagrange single ORIGINAL normal squared norm ORIGINAL product0 := mul(1, 1)

After

Lagrange single ORIGINAL normal squared norm ORIGINAL product0 = 1

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S001

S003 · calculation

Before

Lagrange single ORIGINAL normal squared norm ORIGINAL running sum0 := sum(0, 1)

After

Lagrange single ORIGINAL normal squared norm ORIGINAL running sum0 = 1

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S002

S004 · calculation

Before

Lagrange single ORIGINAL normal squared norm ORIGINAL product1 := mul(24, 24)

After

Lagrange single ORIGINAL normal squared norm ORIGINAL product1 = 576

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S003

S005 · calculation

Before

Lagrange single ORIGINAL normal squared norm ORIGINAL running sum1 := sum(1, 576)

After

Lagrange single ORIGINAL normal squared norm ORIGINAL running sum1 = 577

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S004

S006 · calculation

Before

Lagrange single ORIGINAL normal dot center ORIGINAL product0 := mul(1, 3)

After

Lagrange single ORIGINAL normal dot center ORIGINAL product0 = 3

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S005

S007 · calculation

Before

Lagrange single ORIGINAL normal dot center ORIGINAL running sum0 := sum(0, 3)

After

Lagrange single ORIGINAL normal dot center ORIGINAL running sum0 = 3

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S006

S008 · calculation

Before

Lagrange single ORIGINAL normal dot center ORIGINAL product1 := mul(24, 2)

After

Lagrange single ORIGINAL normal dot center ORIGINAL product1 = 48

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S007

S009 · calculation

Before

Lagrange single ORIGINAL normal dot center ORIGINAL running sum1 := sum(3, 48)

After

Lagrange single ORIGINAL normal dot center ORIGINAL running sum1 = 51

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S008

S010 · calculation

Before

Lagrange single ORIGINAL rhs minus center value := sub(26, 51)

After

Lagrange single ORIGINAL rhs minus center value = -25

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S009

S011 · calculation

Before

Lagrange single ORIGINAL normal displacement := div(-25, 577)

After

Lagrange single ORIGINAL normal displacement = -25/577

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S010

S012 · calculation

Before

Lagrange single ORIGINAL normal shift0 := mul(-25/577, 1)

After

Lagrange single ORIGINAL normal shift0 = -25/577

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S011

S013 · calculation

Before

Lagrange single ORIGINAL solution coordinate0 := sum(3, -25/577)

After

Lagrange single ORIGINAL solution coordinate0 = 1706/577

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S012

S014 · calculation

Before

Lagrange single ORIGINAL normal shift1 := mul(-25/577, 24)

After

Lagrange single ORIGINAL normal shift1 = -600/577

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S013

S015 · calculation

Before

Lagrange single ORIGINAL solution coordinate1 := sum(2, -600/577)

After

Lagrange single ORIGINAL solution coordinate1 = 554/577

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S014

S016 · calculation

Before

Lagrange single ORIGINAL multiplier2tau := mul(2, -25/577)

After

Lagrange single ORIGINAL multiplier2tau = -50/577

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S015

S017 · calculation

Before

Lagrange single ORIGINAL displacement coordinate0 := sub(1706/577, 3)

After

Lagrange single ORIGINAL displacement coordinate0 = -25/577

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S016

S018 · calculation

Before

Lagrange single ORIGINAL objective gradient0 := mul(2, -25/577)

After

Lagrange single ORIGINAL objective gradient0 = -50/577

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S017

S019 · calculation

Before

Lagrange single ORIGINAL displacement coordinate1 := sub(554/577, 2)

After

Lagrange single ORIGINAL displacement coordinate1 = -600/577

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S018

S020 · calculation

Before

Lagrange single ORIGINAL objective gradient1 := mul(2, -600/577)

After

Lagrange single ORIGINAL objective gradient1 = -1200/577

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S019

S021 · calculation

Before

Lagrange single ORIGINAL full feasibility ORIGINAL product0 := mul(1, 1706/577)

After

Lagrange single ORIGINAL full feasibility ORIGINAL product0 = 1706/577

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S020

S022 · calculation

Before

Lagrange single ORIGINAL full feasibility ORIGINAL running sum0 := sum(0, 1706/577)

After

Lagrange single ORIGINAL full feasibility ORIGINAL running sum0 = 1706/577

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S021

S023 · calculation

Before

Lagrange single ORIGINAL full feasibility ORIGINAL product1 := mul(24, 554/577)

After

Lagrange single ORIGINAL full feasibility ORIGINAL product1 = 13296/577

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S022

S024 · calculation

Before

Lagrange single ORIGINAL full feasibility ORIGINAL running sum1 := sum(1706/577, 13296/577)

After

Lagrange single ORIGINAL full feasibility ORIGINAL running sum1 = 26

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S023

S025 · calculation

Before

Lagrange single ORIGINAL lambda times normal0 := mul(-50/577, 1)

After

Lagrange single ORIGINAL lambda times normal0 = -50/577

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S024

S026 · calculation

Before

Lagrange single ORIGINAL lambda times normal1 := mul(-50/577, 24)

After

Lagrange single ORIGINAL lambda times normal1 = -1200/577

Conditions: none

Substitute original roles and established intermediates exactly,not approximations or internally consistent changed operands;extra teaching algebra adds no source-domain gate.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S025

S027 · implies

Before

source roles = [[3, 2], [1, 24], 26, 577, 51, -25/577, [1706/577, 554/577], -50/577, [-50/577, -1200/577]]

After

derived = [Yes, Yes, ANY feasible y=x+v has a dot v=0;f(y)=f(x)+norm(v)^2]

Conditions: none

A nonzero normal gives norm²>0 and tau solves a dot(c+tau a)=rhs.The objective is squared distance WITHOUT1/2,so gradient and lambda contain2.For any feasible y=x+v,the cross term2tau(a dot v)=0 and the objective difference is||v||²>=0.This specified problem has a unique minimum,not general sufficiency of multiplier equations.

Step identifiers and dependencies

Rule: Lagrange_specified_squared_distance_complete_orthogonality_certificate · Uses: G001, S026

Reverse checks

  • S027 · premise_and_result_audit — Reverse-check original data,operands,complete scope and premises;finite witnesses,conditional theorem use and formal proof remain distinct.
  • S026 · premise_and_result_audit — Recompute Lagrange single ORIGINAL lambda times normal1 with exact rational arithmetic, not rounded decimals.
  • S025 · premise_and_result_audit — Recompute Lagrange single ORIGINAL lambda times normal0 with exact rational arithmetic, not rounded decimals.
  • S024 · premise_and_result_audit — Recompute Lagrange single ORIGINAL full feasibility ORIGINAL running sum1 with exact rational arithmetic, not rounded decimals.
  • S023 · premise_and_result_audit — Recompute Lagrange single ORIGINAL full feasibility ORIGINAL product1 with exact rational arithmetic, not rounded decimals.
  • S022 · premise_and_result_audit — Recompute Lagrange single ORIGINAL full feasibility ORIGINAL running sum0 with exact rational arithmetic, not rounded decimals.
  • S021 · premise_and_result_audit — Recompute Lagrange single ORIGINAL full feasibility ORIGINAL product0 with exact rational arithmetic, not rounded decimals.
  • S020 · premise_and_result_audit — Recompute Lagrange single ORIGINAL objective gradient1 with exact rational arithmetic, not rounded decimals.
  • S019 · premise_and_result_audit — Recompute Lagrange single ORIGINAL displacement coordinate1 with exact rational arithmetic, not rounded decimals.
  • S018 · premise_and_result_audit — Recompute Lagrange single ORIGINAL objective gradient0 with exact rational arithmetic, not rounded decimals.
  • S017 · premise_and_result_audit — Recompute Lagrange single ORIGINAL displacement coordinate0 with exact rational arithmetic, not rounded decimals.
  • S016 · premise_and_result_audit — Recompute Lagrange single ORIGINAL multiplier2tau with exact rational arithmetic, not rounded decimals.
  • S015 · premise_and_result_audit — Recompute Lagrange single ORIGINAL solution coordinate1 with exact rational arithmetic, not rounded decimals.
  • S014 · premise_and_result_audit — Recompute Lagrange single ORIGINAL normal shift1 with exact rational arithmetic, not rounded decimals.
  • S013 · premise_and_result_audit — Recompute Lagrange single ORIGINAL solution coordinate0 with exact rational arithmetic, not rounded decimals.
  • S012 · premise_and_result_audit — Recompute Lagrange single ORIGINAL normal shift0 with exact rational arithmetic, not rounded decimals.
  • S011 · premise_and_result_audit — Recompute Lagrange single ORIGINAL normal displacement with exact rational arithmetic, not rounded decimals.
  • S010 · premise_and_result_audit — Recompute Lagrange single ORIGINAL rhs minus center value with exact rational arithmetic, not rounded decimals.
  • S009 · premise_and_result_audit — Recompute Lagrange single ORIGINAL normal dot center ORIGINAL running sum1 with exact rational arithmetic, not rounded decimals.
  • S008 · premise_and_result_audit — Recompute Lagrange single ORIGINAL normal dot center ORIGINAL product1 with exact rational arithmetic, not rounded decimals.
  • S007 · premise_and_result_audit — Recompute Lagrange single ORIGINAL normal dot center ORIGINAL running sum0 with exact rational arithmetic, not rounded decimals.
  • S006 · premise_and_result_audit — Recompute Lagrange single ORIGINAL normal dot center ORIGINAL product0 with exact rational arithmetic, not rounded decimals.
  • S005 · premise_and_result_audit — Recompute Lagrange single ORIGINAL normal squared norm ORIGINAL running sum1 with exact rational arithmetic, not rounded decimals.
  • S004 · premise_and_result_audit — Recompute Lagrange single ORIGINAL normal squared norm ORIGINAL product1 with exact rational arithmetic, not rounded decimals.
  • S003 · premise_and_result_audit — Recompute Lagrange single ORIGINAL normal squared norm ORIGINAL running sum0 with exact rational arithmetic, not rounded decimals.
  • S002 · premise_and_result_audit — Recompute Lagrange single ORIGINAL normal squared norm ORIGINAL product0 with exact rational arithmetic, not rounded decimals.
  • S001 · premise_and_result_audit — Reverse-check original data,operands,complete scope and premises;finite witnesses,conditional theorem use and formal proof remain distinct.

Result

([3, 2], [1, 24], 26, -25/577, [1706/577, 554/577], -50/577, [-50/577, -1200/577], Yes, Yes, squared_distance_with_one_regular_linear_constraint_solved_exactly)

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: 00d08999ade46712f13910bc85a5ac818ba8af4baac20f26fb2cb100e8331a00
  • candidate record SHA-256: f66fb9ffc25ffe421634cc7a304bde121698d8b4824d6f3c3be8ef5909809ecc
  • semantic review receipt SHA-256: 0a76d8e93c08bb16998a0483f3dfc0504f269fc3e1982e6cd868cab0a2856d54
  • question-first witness SHA-256: 09127b736c225714dfa0b7ceb0e6a6e66df27438b480cad8217d3c2f99ce9437
  • Lean: NOT_RUN · human review: NOT_PERFORMED
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