# Question 13088: Evaluate a Possibly Rectangular Real Linear Map

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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.

R0025-13088 · q-20261014-advance-20261027-r05-general-linear-map-0013



## Original question and givens

Use the complete rectangular matrix A=[[0, 2, -2], [0, 0, 2]] as a map from its column-coordinate space to its row-coordinate space, both over the reals. Matrix distributivity is a universal coordinate certificate. All vectors and any bias must have their respective input/output dimensions. Finite samples do not establish linearity of an arbitrary black box, or imply injectivity, surjectivity, boundedness or continuity beyond the stated claim. vector=[-1, 0, 2]. Give (matrix,vector,image).


- G001 — Use the complete rectangular matrix A=[[0, 2, -2], [0, 0, 2]] as a map from its column-coordinate space to its row-coordinate space, both over the reals. Matrix distributivity is a universal coordinate certificate. All vectors and any bias must have their respective input/output dimensions. Finite samples do not establish linearity of an arbitrary black box, or imply injectivity, surjectivity, boundedness or continuity beyond the stated claim. vector=[-1, 0, 2]. Give (matrix,vector,image).





## 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-general-linear-map](https://ocme.evemisslab.com/en/mko/mko-general-linear-map/)





## Step-by-step derivation

S001 · impliesBefore

requested matrix image:matrix=[[0, 2, -2], [0, 0, 2]];input=[-1, 0, 2]

After

R^3->R^2;each output is its original row dot input

Conditions: none

Input dimension is the column count and output dimension the row count.The matrix may be rectangular;do not transpose it or invent coordinates.

Step identifiers and dependenciesRule: rectangular_linear_map_source_target_roles · Uses: G001





S002 · calculationBefore

requested matrix image row0 column0 term := mul(0, -1)

After

requested matrix image row0 column0 term = 0

Conditions: none

Compute exactly from original roles and established intermediates,retaining coefficients,coordinates,order and signs.

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





S003 · calculationBefore

requested matrix image row0 column1 term := mul(2, 0)

After

requested matrix image row0 column1 term = 0

Conditions: none

Compute exactly from original roles and established intermediates,retaining coefficients,coordinates,order and signs.

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





S004 · calculationBefore

requested matrix image row0 column2 term := mul(-2, 2)

After

requested matrix image row0 column2 term = -4

Conditions: none

Compute exactly from original roles and established intermediates,retaining coefficients,coordinates,order and signs.

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





S005 · calculationBefore

requested matrix image row0 sum := sum(0, 0, -4)

After

requested matrix image row0 sum = -4

Conditions: none

Compute exactly from original roles and established intermediates,retaining coefficients,coordinates,order and signs.

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





S006 · calculationBefore

requested matrix image row1 column0 term := mul(0, -1)

After

requested matrix image row1 column0 term = 0

Conditions: none

Compute exactly from original roles and established intermediates,retaining coefficients,coordinates,order and signs.

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





S007 · calculationBefore

requested matrix image row1 column1 term := mul(0, 0)

After

requested matrix image row1 column1 term = 0

Conditions: none

Compute exactly from original roles and established intermediates,retaining coefficients,coordinates,order and signs.

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





S008 · calculationBefore

requested matrix image row1 column2 term := mul(2, 2)

After

requested matrix image row1 column2 term = 4

Conditions: none

Compute exactly from original roles and established intermediates,retaining coefficients,coordinates,order and signs.

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





S009 · calculationBefore

requested matrix image row1 sum := sum(0, 0, 4)

After

requested matrix image row1 sum = 4

Conditions: none

Compute exactly from original roles and established intermediates,retaining coefficients,coordinates,order and signs.

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









## Reverse checks


- S009 · premise_and_result_audit — Recompute requested matrix image row1 sum with exact rational arithmetic, not rounded decimals.
- S008 · premise_and_result_audit — Recompute requested matrix image row1 column2 term with exact rational arithmetic, not rounded decimals.
- S007 · premise_and_result_audit — Recompute requested matrix image row1 column1 term with exact rational arithmetic, not rounded decimals.
- S006 · premise_and_result_audit — Recompute requested matrix image row1 column0 term with exact rational arithmetic, not rounded decimals.
- S005 · premise_and_result_audit — Recompute requested matrix image row0 sum with exact rational arithmetic, not rounded decimals.
- S004 · premise_and_result_audit — Recompute requested matrix image row0 column2 term with exact rational arithmetic, not rounded decimals.
- S003 · premise_and_result_audit — Recompute requested matrix image row0 column1 term with exact rational arithmetic, not rounded decimals.
- S002 · premise_and_result_audit — Recompute requested matrix image row0 column0 term 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

([[0, 2, -2], [0, 0, 2]], [-1, 0, 2], [-4, 4])

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: 3eb95463e994d6e5faee476d336edae30738aa29492f57cf4da3a6c4052e7dba
- candidate record SHA-256: 3a03bbf59da7ea169d2211f0d295f0936919ab8e7b29f4d79b3e388660ec4d3a
- semantic review receipt SHA-256: 0e51c2bf621e6e998415fdd75d260464e625cecd5894a230c9f09553249551c5
- question-first witness SHA-256: ceb79401a62782c9f7e5ed86afee9b1a71455f799bd24cf485cba7aa8ecaca8a
- Lean: NOT_RUN · human review: NOT_PERFORMED

[Same-source full JSON](https://ocme.evemisslab.com/data/question-derivations/questions/q-20261014-advance-20261027-r05-general-linear-map-0013.json)




