# Question 24493: The Symbolic Gradient Keeps Every Euclidean Coordinate in Order

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This teaching derivation has second-context AI mathematical and bilingual semantic review, limited to the model and assumptions stated in this question. It has no human review or new Lean proof and does not promote the original question or MKO to Canonical truth.

R0047-24493 · q-20261015-advance-20261113-r06-gradient-vector-0018



## Original question and givens

Use dimension=3, raw polynomial terms=[[18, [2, 1, 0]], [19, [0, 1, 1]], [1, [0, 0, 0]]], each [rational coefficient,ordered exponent vector]. Coefficients may be integers or [numerator,denominator]. Exponent/point arities equal the dimension. Combine equal monomials and remove zero coefficients before the canonical symbolic output. Coordinate order and the standard Euclidean basis/metric are fixed. Give (dimension, canonical_terms, coordinate_derivative_polynomials, certificate).


- G001 — Use dimension=3, raw polynomial terms=[[18, [2, 1, 0]], [19, [0, 1, 1]], [1, [0, 0, 0]]], each [rational coefficient,ordered exponent vector]. Coefficients may be integers or [numerator,denominator]. Exponent/point arities equal the dimension. Combine equal monomials and remove zero coefficients before the canonical symbolic output. Coordinate order and the standard Euclidean basis/metric are fixed. Give (dimension, canonical_terms, coordinate_derivative_polynomials, certificate).





## 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.


- [mko-gradient-vector](https://ocme.evemisslab.com/en/mko/mko-gradient-vector/)





## Step-by-step derivation

S001 · impliesBefore

source roles = [gradient-symbolic-polynomial]

After

derived = [[dimension, canonical_terms, coordinate_derivative_polynomials, certificate]]

Conditions: none

List the source field order without JavaScript.Gradient boundary uses its original mode to choose6,8 or7 fields;no padding or answer-derived mode.

Step identifiers and dependenciesRule: source_ordered_fields_without_JS · Uses: G001





S002 · calculationBefore

Gradient ORIGINAL monomial coefficient sum0 := sum(0, 18)

After

Gradient ORIGINAL monomial coefficient sum0 = 18

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S001





S003 · impliesBefore

source roles = [0, 3, [2, 1, 0], 18]

After

derived = [18]

Conditions: none

Combine only identical ordered exponent vectors;remove zeros after combining and keep fixed Euclidean coordinate order.

Step identifiers and dependenciesRule: Gradient_original_term_position_and_exponent_arity · Uses: G001, S002





S004 · calculationBefore

Gradient ORIGINAL monomial coefficient sum1 := sum(0, 19)

After

Gradient ORIGINAL monomial coefficient sum1 = 19

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S003





S005 · impliesBefore

source roles = [1, 3, [0, 1, 1], 19]

After

derived = [19]

Conditions: none

Combine only identical ordered exponent vectors;remove zeros after combining and keep fixed Euclidean coordinate order.

Step identifiers and dependenciesRule: Gradient_original_term_position_and_exponent_arity · Uses: G001, S004





S006 · calculationBefore

Gradient ORIGINAL monomial coefficient sum2 := sum(0, 1)

After

Gradient ORIGINAL monomial coefficient sum2 = 1

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S005





S007 · impliesBefore

source roles = [2, 3, [0, 0, 0], 1]

After

derived = [1]

Conditions: none

Combine only identical ordered exponent vectors;remove zeros after combining and keep fixed Euclidean coordinate order.

Step identifiers and dependenciesRule: Gradient_original_term_position_and_exponent_arity · Uses: G001, S006





S008 · impliesBefore

source roles = [[[18, [2, 1, 0]], [19, [0, 1, 1]], [1, [0, 0, 0]]]]

After

derived = [3, [[1, [0, 0, 0]], [19, [0, 1, 1]], [18, [2, 1, 0]]]]

Conditions: none

Use source English canonical-exponent order,not numeric tuple order.Complete cancellation may yield an empty canonical list for the zero polynomial.

Step identifiers and dependenciesRule: Gradient_canonical_nonzero_polynomial_terms_source_order · Uses: G001, S007





S009 · impliesBefore

source roles = [0, 0, [0, 0, 0], 1]

After

derived = [0]

Conditions: none

Exponent0 means derivative0 in this coordinate,without omitting other coordinates.

Step identifiers and dependenciesRule: Gradient_constant_in_coordinate_derivative_zero · Uses: G001, S008





S010 · impliesBefore

source roles = [0, 1, [0, 1, 1], 19]

After

derived = [0]

Conditions: none

Exponent0 means derivative0 in this coordinate,without omitting other coordinates.

Step identifiers and dependenciesRule: Gradient_constant_in_coordinate_derivative_zero · Uses: G001, S009





S011 · calculationBefore

Gradient axis0 term2 power-rule coefficient := mul(18, 2)

After

Gradient axis0 term2 power-rule coefficient = 36

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S010





S012 · calculationBefore

Gradient axis0 derivative combine2 := sum(0, 36)

After

Gradient axis0 derivative combine2 = 36

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S011





S013 · impliesBefore

source roles = [0, 2, [2, 1, 0], 18, 2]

After

derived = [[1, 1, 0], 36]

Conditions: none

Hold the other variables fixed:the coefficient becomes ck and only this coordinate exponent decreases by1.

Step identifiers and dependenciesRule: Gradient_coordinate_power_rule_ordered_exponents · Uses: G001, S012





S014 · impliesBefore

source roles = [1, 0, [0, 0, 0], 1]

After

derived = [0]

Conditions: none

Exponent0 means derivative0 in this coordinate,without omitting other coordinates.

Step identifiers and dependenciesRule: Gradient_constant_in_coordinate_derivative_zero · Uses: G001, S013





S015 · calculationBefore

Gradient axis1 term1 power-rule coefficient := mul(19, 1)

After

Gradient axis1 term1 power-rule coefficient = 19

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S014





S016 · calculationBefore

Gradient axis1 derivative combine1 := sum(0, 19)

After

Gradient axis1 derivative combine1 = 19

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S015





S017 · impliesBefore

source roles = [1, 1, [0, 1, 1], 19, 1]

After

derived = [[0, 0, 1], 19]

Conditions: none

Hold the other variables fixed:the coefficient becomes ck and only this coordinate exponent decreases by1.

Step identifiers and dependenciesRule: Gradient_coordinate_power_rule_ordered_exponents · Uses: G001, S016





S018 · calculationBefore

Gradient axis1 term2 power-rule coefficient := mul(18, 1)

After

Gradient axis1 term2 power-rule coefficient = 18

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S017





S019 · calculationBefore

Gradient axis1 derivative combine2 := sum(0, 18)

After

Gradient axis1 derivative combine2 = 18

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S018





S020 · impliesBefore

source roles = [1, 2, [2, 1, 0], 18, 1]

After

derived = [[2, 0, 0], 18]

Conditions: none

Hold the other variables fixed:the coefficient becomes ck and only this coordinate exponent decreases by1.

Step identifiers and dependenciesRule: Gradient_coordinate_power_rule_ordered_exponents · Uses: G001, S019





S021 · impliesBefore

source roles = [2, 0, [0, 0, 0], 1]

After

derived = [0]

Conditions: none

Exponent0 means derivative0 in this coordinate,without omitting other coordinates.

Step identifiers and dependenciesRule: Gradient_constant_in_coordinate_derivative_zero · Uses: G001, S020





S022 · calculationBefore

Gradient axis2 term1 power-rule coefficient := mul(19, 1)

After

Gradient axis2 term1 power-rule coefficient = 19

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S021





S023 · calculationBefore

Gradient axis2 derivative combine1 := sum(0, 19)

After

Gradient axis2 derivative combine1 = 19

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S022





S024 · impliesBefore

source roles = [2, 1, [0, 1, 1], 19, 1]

After

derived = [[0, 1, 0], 19]

Conditions: none

Hold the other variables fixed:the coefficient becomes ck and only this coordinate exponent decreases by1.

Step identifiers and dependenciesRule: Gradient_coordinate_power_rule_ordered_exponents · Uses: G001, S023





S025 · impliesBefore

source roles = [2, 2, [2, 1, 0], 18]

After

derived = [0]

Conditions: none

Exponent0 means derivative0 in this coordinate,without omitting other coordinates.

Step identifiers and dependenciesRule: Gradient_constant_in_coordinate_derivative_zero · Uses: G001, S024





S026 · impliesBefore

source roles = [3, [[1, [0, 0, 0]], [19, [0, 1, 1]], [18, [2, 1, 0]]]]

After

derived = [[[[36, [1, 1, 0]]], [[19, [0, 0, 1]], [18, [2, 0, 0]]], [[19, [0, 1, 0]]]]]

Conditions: none

The gradient contains all d ordered component polynomials.Polynomial differentiability makes this Euclidean vector represent the differential,not a sampled single direction.

Step identifiers and dependenciesRule: Gradient_ALL_ordered_coordinate_polynomials · Uses: G001, S025









## Reverse checks


- S026 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S025 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S024 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S023 · premise_and_result_audit — Recompute Gradient axis2 derivative combine1 with exact rational arithmetic, not rounded decimals.
- S022 · premise_and_result_audit — Recompute Gradient axis2 term1 power-rule coefficient with exact rational arithmetic, not rounded decimals.
- S021 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S020 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S019 · premise_and_result_audit — Recompute Gradient axis1 derivative combine2 with exact rational arithmetic, not rounded decimals.
- S018 · premise_and_result_audit — Recompute Gradient axis1 term2 power-rule coefficient with exact rational arithmetic, not rounded decimals.
- S017 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S016 · premise_and_result_audit — Recompute Gradient axis1 derivative combine1 with exact rational arithmetic, not rounded decimals.
- S015 · premise_and_result_audit — Recompute Gradient axis1 term1 power-rule coefficient with exact rational arithmetic, not rounded decimals.
- S014 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S013 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S012 · premise_and_result_audit — Recompute Gradient axis0 derivative combine2 with exact rational arithmetic, not rounded decimals.
- S011 · premise_and_result_audit — Recompute Gradient axis0 term2 power-rule coefficient with exact rational arithmetic, not rounded decimals.
- S010 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S009 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S008 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- 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 Gradient ORIGINAL monomial coefficient sum2 with exact rational arithmetic, not rounded decimals.
- S005 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S004 · premise_and_result_audit — Recompute Gradient ORIGINAL monomial coefficient sum1 with exact rational arithmetic, not rounded decimals.
- S003 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S002 · premise_and_result_audit — Recompute Gradient ORIGINAL monomial coefficient sum0 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.





## Result

(3, [[1, [0, 0, 0]], [19, [0, 1, 1]], [18, [2, 1, 0]]], [[[36, [1, 1, 0]]], [[19, [0, 0, 1]], [18, [2, 0, 0]]], [[19, [0, 1, 0]]]], standard_Euclidean_coordinate_order_preserved)

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: 02987fd4d14bea3018572913eb203b24b647d973c3b4ee902b3eed49feb8d6bd
- candidate record SHA-256: 1c76334bd318cd488114490a3e84cd69084e87c08ef1603f8349932b97e23bb4
- semantic review receipt SHA-256: 9b43b9823e9bd2478d6caa5b57ffed161c2c8956af86974e901d5662ad994386
- question-first witness SHA-256: eb97596068e2d5648033bab2b8f6ca9b653bbe8cb77c0f8e1d16d0c40e46f50b
- Lean: NOT_RUN · human review: NOT_PERFORMED

[Same-source full JSON](https://ocme.evemisslab.com/data/question-derivations/questions/q-20261015-advance-20261113-r06-gradient-vector-0018.json)




