Explore related knowledge and questions →

Question 11218: Independence and Spanning Are Separate Plane-Basis Obligations

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 57

← Question derivation index · Original question batch

R0021-11218 · q-20261013-advance-20261024-r01-linear-independence-basis-0043

Original question and givens

Use the explicitly supplied finite integer-coordinate vector family in a real coordinate space. Preserve vector order and coefficient pairing. Rank is computed by exact rational elimination; a basis requires both independence and spanning the declared space, not just one condition. vectors=[[1, 5], [0, 1]] must all have dimension 2. Give (vectors,rank,independent?,spans R²?,is an R² basis?). Spanning requires rank 2; a basis additionally requires exactly two independent vectors.

  • G001 — Use the explicitly supplied finite integer-coordinate vector family in a real coordinate space. Preserve vector order and coefficient pairing. Rank is computed by exact rational elimination; a basis requires both independence and spanning the declared space, not just one condition. vectors=[[1, 5], [0, 1]] must all have dimension 2. Give (vectors,rank,independent?,spans R²?,is an R² basis?). Spanning requires rank 2; a basis additionally requires exactly two independent vectors.

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

ordered column vectors=[[1, 5], [0, 1]]

After

homogeneous coefficient matrix=[[1, 0], [5, 1]];unknown count=2

Conditions: none

Use vectors as columns in original order.Independence means this homogeneous system has only the zero coefficient solution;row operations must preserve its solution set.

Step identifiers and dependencies

Rule: column_matrix_homogeneous_equations · Uses: G001

S002 · implies

Before

matrix=[[1, 0], [5, 1]];next pivot column=0;swap rows 0,0

After

matrix=[[1, 0], [5, 1]]

Conditions: none

Swapping rows only reorders equations;the same swap reverses it.It does not exchange the original vector columns.

Step identifiers and dependencies

Rule: invertible_row_swap · Uses: G001, S001

S003 · calculation

Before

pivot0 normalized column0 := div(1, 1)

After

pivot0 normalized column0 = 1

Conditions: none

Compute exactly with this step's specified roles,retaining signs,denominators and original pairings.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S002

S004 · calculation

Before

pivot0 normalized column1 := div(0, 1)

After

pivot0 normalized column1 = 0

Conditions: none

Compute exactly with this step's specified roles,retaining signs,denominators and original pairings.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S003

S005 · implies

Before

row=0;old row=[1, 0];nonzero divisor=1

After

new row=[1, 0]

Conditions: none

The pivot is known nonzero before division of the whole row.Multiplication by it reverses the operation,so the homogeneous solution set is unchanged.

Step identifiers and dependencies

Rule: nonzero_row_scaling_solution_equivalence · Uses: G001, S004

S006 · calculation

Before

eliminate pivot0 row1 column0 scaled := mul(5, 1)

After

eliminate pivot0 row1 column0 scaled = 5

Conditions: none

Compute exactly with this step's specified roles,retaining signs,denominators and original pairings.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S005

S007 · calculation

Before

eliminate pivot0 row1 column0 residual := sub(5, 5)

After

eliminate pivot0 row1 column0 residual = 0

Conditions: none

Compute exactly with this step's specified roles,retaining signs,denominators and original pairings.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S006

S008 · calculation

Before

eliminate pivot0 row1 column1 scaled := mul(5, 0)

After

eliminate pivot0 row1 column1 scaled = 0

Conditions: none

Compute exactly with this step's specified roles,retaining signs,denominators and original pairings.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S007

S009 · calculation

Before

eliminate pivot0 row1 column1 residual := sub(1, 0)

After

eliminate pivot0 row1 column1 residual = 1

Conditions: none

Compute exactly with this step's specified roles,retaining signs,denominators and original pairings.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S008

S010 · implies

Before

target row=1;old=[5, 1];pivot row=[1, 0];factor=5

After

new row=[0, 1];matrix=[[1, 0], [0, 1]]

Conditions: none

Subtract factor times the pivot row to eliminate this entry.Adding it back recovers the original equation;no solutions are created or lost.

Step identifiers and dependencies

Rule: invertible_pivot_row_subtraction · Uses: G001, S009

S011 · implies

Before

matrix=[[1, 0], [0, 1]];next pivot column=1;swap rows 1,1

After

matrix=[[1, 0], [0, 1]]

Conditions: none

Swapping rows only reorders equations;the same swap reverses it.It does not exchange the original vector columns.

Step identifiers and dependencies

Rule: invertible_row_swap · Uses: G001, S010

S012 · calculation

Before

pivot1 normalized column0 := div(0, 1)

After

pivot1 normalized column0 = 0

Conditions: none

Compute exactly with this step's specified roles,retaining signs,denominators and original pairings.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S011

S013 · calculation

Before

pivot1 normalized column1 := div(1, 1)

After

pivot1 normalized column1 = 1

Conditions: none

Compute exactly with this step's specified roles,retaining signs,denominators and original pairings.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S012

S014 · implies

Before

row=1;old row=[0, 1];nonzero divisor=1

After

new row=[0, 1]

Conditions: none

The pivot is known nonzero before division of the whole row.Multiplication by it reverses the operation,so the homogeneous solution set is unchanged.

Step identifiers and dependencies

Rule: nonzero_row_scaling_solution_equivalence · Uses: G001, S013

S015 · implies

Before

reduced matrix=[[1, 0], [0, 1]];pivot columns=[0, 1];unknown count=2

After

rank=2;free variables=0;independent=Yes

Conditions: none

Rank is the pivot count.If every column pivots,the homogeneous solution is zero only.Otherwise set one free variable to1,the other free variables to0,and back-substitute pivot variables to obtain a nontrivial zero combination.

Step identifiers and dependencies

Rule: rank_free_variables_and_independence · Uses: G001, S014

S016 · implies

Before

ambient space=R2;rank=2;family size=2

After

independent=Yes;spans_R2=Yes;basis_R2=Yes

Conditions: none

Invertible row operations preserve image dimension;rank2 is required to span R².An independent singleton does not span the plane,and redundant spanning vectors are not a basis.

Step identifiers and dependencies

Rule: basis_independence_and_spanning_separate · Uses: G001, S015

Reverse checks

  • S016 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
  • S015 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
  • 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 — Recompute pivot1 normalized column1 with exact rational arithmetic, not rounded decimals.
  • S012 · premise_and_result_audit — Recompute pivot1 normalized column0 with exact rational arithmetic, not rounded decimals.
  • S011 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
  • 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 — Recompute eliminate pivot0 row1 column1 residual with exact rational arithmetic, not rounded decimals.
  • S008 · premise_and_result_audit — Recompute eliminate pivot0 row1 column1 scaled with exact rational arithmetic, not rounded decimals.
  • S007 · premise_and_result_audit — Recompute eliminate pivot0 row1 column0 residual with exact rational arithmetic, not rounded decimals.
  • S006 · premise_and_result_audit — Recompute eliminate pivot0 row1 column0 scaled 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 pivot0 normalized column1 with exact rational arithmetic, not rounded decimals.
  • S003 · premise_and_result_audit — Recompute pivot0 normalized column0 with exact rational arithmetic, not rounded decimals.
  • S002 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
  • S001 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.

Result

([[1, 5], [0, 1]], 2, Yes, Yes, Yes)

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: e1dced685aafbc110deae05c00bed237417d02476198a547cd3891ba0d67de0e
  • candidate record SHA-256: 5783f47257984a9352d9c752709f770a65df5ce859f41435830f570ae79bff74
  • semantic review receipt SHA-256: 47d23d3735987d68e27733b051bdfa80a3616d44fb223b82bf2e6c8e46d49258
  • question-first witness SHA-256: a857db558000724020d2d5e815cb6bc3e2c9e2933df295bf33eb478d3c695139
  • Lean: NOT_RUN · human review: NOT_PERFORMED
Same-source full JSON