HL Matrix Arithmetic, Inverse & Sim Equations 1.14

What are matrices and how do we calculate with them?

On this page you can find a set of videos, created by Dr James Tanton, for the topic AHL 1.14 that provide an intuitive, conceptual insight into what matrices are, why they are useful and how we calculate with them. Calculating a matrix's inverse and solving simultaneous equations using matrices are also covered [note: the film 'The Matrix' (pause the clip at 34, 58, 66/67, 68/69 and 80 seconds to see 'the matrix'!) was not created by James, nor us! Tok: what's the link between the film and this topic?]

A practice question, 68 marks of IB Exam Style questions and a bonus section on Associativity of Matrices follow at the end of the videos.

Matrices 1: A Natural Appearance/utility

SOLUTIONS to Exam style questions</a></p></div><div class="pinkBg"><h2><a href="Browse server to select file" target="_blank" title="Activities"><img class="ico" src="https://assets.inthinking.net/teaching-material-icons/activities.svg" /> </a><a href="/media/ib/mathapplications/ai-files/1-number-and-algebra/hlmatrixarithmetic/matrices-associativity-bonusresource.pdf" target="_blank">Bonus Material: Matrix Multiplication is Associative </a></h2><p><strong>Associative: </strong>re-arranging which items you bracket won't change the outcome, as with equations that <strong>only</strong> contain multiplication or <strong>only</strong> addition, but <strong>not </strong>in a calculation with a mix of multiplications and additions.</p><p>Mutiplication and addition do not, combined, show associativity e.g. (1+1)x2 ≠ 1+(1x2) [<strong>not</strong> associative] but (3x4)x5 = 3x(4x5) [associative].</p></div></section></article><section id="media-extras"><div style="border-top: solid 1px #eee;border-bottom: solid 1px #eee;padding: 4px 0 4px 0;line-height: 1em;color: #666;font-size: .8em"><small><em>All materials on this website are for the exclusive use of teachers and students at subscribing schools for the period of their subscription. 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IBDP Maths: Applications & Interpretation

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HL Matrix Arithmetic, Inverse & Sim Equations 1.14

What are matrices and how do we calculate with them?

Matrices 1: A Natural Appearance/utility

IBDP Maths: Applications & Interpretation

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HL Matrix Arithmetic, Inverse & Sim Equations 1.14

What are matrices and how do we calculate with them?

Matrices 1: A Natural Appearance/utility