Explore related knowledge and questions →

Question 2726: Area of a Half-Open Rectangle with Nonnegative Dimensions

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 14

← Question derivation index · Original question batch

R0004-02726 · q-20261005-advance-20261006-r06-area-0001

Original question and givens

Use one equal-unit orthonormal Euclidean Cartesian frame. The half-open rectangle [0,0)×[0,3) has width 0 and height 3, both nonnegative. Find its area in squared length units.

  • G001 — Use one equal-unit orthonormal Euclidean Cartesian frame. The half-open rectangle [0,0)×[0,3) has width 0 and height 3, both nonnegative. Find its area in squared length units.

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

orthonormal equal-length coordinate units;half-open regions

After

area in squared length units

Conditions: none

Axes are orthogonal with equal length units;half-open boundaries make adjacent unit cells disjoint.Area uses squared units,not length units.

Step identifiers and dependencies

Rule: half_open_area_convention · Uses: G001

S002 · calculation

Before

rectangle area := mul(0, 3)

After

rectangle area = 0

Conditions: none

Multiply nonnegative width by height;adding the side lengths does not give area.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S001

S003 · implies

Before

w=0; h=3

After

area=0; empty=Yes

Conditions: none

A zero side is an allowed empty region;this is not a perimeter calculation.

Step identifiers and dependencies

Rule: rectangle_area_boundary · Uses: G001, S002

Reverse checks

  • 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 rectangle area 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

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: a6b0fefd723f806f969f9e9c3b9c2ebcea0ebe55e7f33c44a6abf2fa0abfdd08
  • candidate record SHA-256: bab6a4141d2006e1005cddde163dc34f26a10b6f5363c1f7bab85b39c1c7a7a6
  • semantic review receipt SHA-256: 312ae86315346b8955842a547cb2d09246e1f826755f72c2a51f042e5c7d5c56
  • question-first witness SHA-256: 831f449ed41ff9144a290e534aa32adf7252d15b81c16ed5886a7dfd65dee70c
  • Lean: NOT_RUN · human review: NOT_PERFORMED
Same-source full JSON