Ivan Shishkin, Rye (1878)

Problems/Linear algebraExerciseReviewed

Equality of simple matrices

by Ancient Tree·
4
Difficulty scaleÉchelle de difficulté

This score reflects both the level of the required concepts and the difficulty of the solution.Ce score tient compte à la fois du niveau des notions nécessaires et de la difficulté de la résolution.

  1. 110First steps / middle schoolPremiers pas / collège
  2. 1125Beginner / high schoolDébutant / lycée
  3. 2650Intermediate / undergraduateIntermédiaire / licence
  4. 5170Advanced / graduateAvancé / master
  5. 7190Expert / specializedExpert / spécialisé
  6. 91100Research levelNiveau recherche
These levels are approximate guides.Ces niveaux sont des repères approximatifs.
·
English
EnglishFrançais

Here are three matrices:
A=(100123),B=(1001),C=(102013)A=\left(\begin{array}{ll} 1 & 0 \\ 0 & 1 \\ 2 & 3 \end{array}\right), \quad B=\left(\begin{array}{ll} 1 & 0 \\ 0 & 1 \end{array}\right),\quad C=\left(\begin{array}{lll} 1 & 0 & 2 \\ 0 & 1 & 3 \end{array}\right)Are they distinct?

I solved itMark it doneAdd to my listKeep it in your list

Solutions

1
Reveal solutionsAre you sure? Give it a try first.

Solution by Ancient Tree

Discussions0 useful votes

Yes, A,B,CA,B,C are three distinct matrices (meaning that ABA\neq B, ACA\neq C, and BCB\neq C), simply because their entries are different.
One might be tempted to say that AA and CC do have the same coefficients! But their dimensions are different, so they are not the same matrices.

Report

For an unclear, ambiguous, or possibly incorrect statement, please use the Discussion tab on the right. Report content that needs moderator intervention, such as dangerous, clearly non-mathematical, or plagiarized content.