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Let

\n \n \n \n

\\[A = \\left(\\begin{array}{rrr} \\var{a11} & \\var{a12} & \\var{a13}\\\\ \\var{a21} & \\var{a22} & \\var{a23}\\\\ \\var{a31} & \\var{a32} & \\var{a33}\\\\\n \n \\end{array}\\right),\\;\\;\\;\\;\n \n B= \\left(\\begin{array}{rrr} \\var{b11} & \\var{b12} & \\var{b13}\\\\ \\var{b21} & \\var{b22} & \\var{b23}\\\\ \\var{b31} & \\var{b32} & \\var{b33}\\\\\n \n \\end{array}\\right),\\;\\;\\;\\;\n \n v= \\left(\\begin{array}{r} \\var{v1}\\\\ \\var{v2} \\\\ \\var{v3} \\end{array}\\right),\\;\\;\\;\\;\n \n w= \\left(\\begin{array}{r} \\var{w1}\\\\ \\var{w2} \\\\ \\var{w3} \\end{array}\\right)\\]

\n \n \n \n

Find the following products:

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n
\\[ Av=\\left( \\begin{matrix} \\phantom{.}\\\\ \\phantom{.}\\\\ \\phantom{.}\\\\ \\phantom{.}\\\\ \\end{matrix} \\right.\\] [[0]] \\[\\left) \\begin{matrix} \\phantom{.} \\\\ \\phantom{.}\\\\ \\phantom{.}\\\\ \\phantom{.}\\\\ \\end{matrix} \\right.\\]
[[1]]
[[2]]
\\[ Bw=\\left( \\begin{matrix} \\phantom{.}\\\\ \\phantom{.}\\\\ \\phantom{.}\\\\ \\phantom{.}\\\\ \\end{matrix} \\right.\\] [[3]] \\[\\left) \\begin{matrix} \\phantom{.} \\\\ \\phantom{.}\\\\ \\phantom{.}\\\\ \\phantom{.}\\\\ \\end{matrix} \\right.\\]
[[4]]
[[5]]
\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n
\\[BA=\\left( \\begin{matrix} \\phantom{.}\\\\ \\phantom{.}\\\\ \\phantom{.}\\\\ \\phantom{.}\\\\ \\end{matrix} \\right.\\] [[6]] [[7]] [[8]] \\[\\left) \\begin{matrix} \\phantom{.} \\\\ \\phantom{.}\\\\ \\phantom{.}\\\\ \\phantom{.}\\\\ \\end{matrix} \\right.\\]
[[9]] [[10]] [[11]]
[[12]] [[13]] [[14]]
\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n
\\[AB=\\left( \\begin{matrix} \\phantom{.}\\\\ \\phantom{.}\\\\ \\phantom{.}\\\\ \\phantom{.}\\\\ \\end{matrix} \\right.\\] [[15]] [[16]] [[17]] \\[\\left) \\begin{matrix} \\phantom{.} \\\\ \\phantom{.}\\\\ \\phantom{.}\\\\ \\phantom{.}\\\\ \\end{matrix} \\right.\\]
[[18]] [[19]] [[20]]
[[21]] [[22]] [[23]]
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Consider the following matrices together with the matrices from the first part of the question.

\n

\\[\\begin{eqnarray}&C=& \\var{mac},\\;\\;\\;\\; &D=& \\var{mad},\\;\\;\\; \\;&E= &\\var{mae}\\\\&F=& \\left(\\begin{array}{rr} \\var{w1} & \\var{a12}\\\\ \\var{w2} & \\var{b23} \\\\ \\var{w3} & \\var{w2} \\\\\\var{v1} & \\var{b12}\\\\ 0 & \\var{-w2} \\end{array}\\right),\\;\\;\\;\\;&G=&\\var{mag},\\;\\;\\;\\;&H=&\\var{mah} \\end{eqnarray}\\]

\n

Which of the following products of matrices can be calculated?

\n

[[0]]

\n

Please note that for every correct answer you get 0.5 marks and for every incorrect answer 0.5 is taken away. The minimum mark you can get is 0.

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$CD$

", "

$DC$

", "

$EF$

", "

$FE$

", "

$BC$

", "

$AE$

", "

$GH$

", "

$HE$

", "

$AG$

", "

$GB$

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Elementary Exercises in multiplying matrices. 

", "notes": "\n \t\t \t\t

5/07/2012:

\n \t\t \t\t

Added tags.

\n \t\t \t\t

Question appears to be working correctly.

\n \t\t \t\t

 

\n \t\t \n \t\t", "licence": "Creative Commons Attribution 4.0 International"}, "variablesTest": {"maxRuns": 100, "condition": ""}, "statement": "

Answer the following questions on matrices.

\n

 

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"b12": {"name": "b12", "description": "", "templateType": "anything", "group": "Ungrouped variables", "definition": "random(0,1)"}, "a13": {"name": "a13", "description": "", "templateType": "anything", "group": "Ungrouped variables", "definition": "random(1..2)"}, "c11": {"name": "c11", "description": "", "templateType": "anything", "group": "Ungrouped variables", "definition": "random(-2..2)"}, "w3": {"name": "w3", "description": "", "templateType": "anything", "group": "Ungrouped variables", "definition": "random(-4..4)"}, "ba22": {"name": "ba22", "description": "", "templateType": "anything", "group": "Ungrouped variables", "definition": "b21*a12+b22*a22+b23*a32"}, "s2": {"name": "s2", "description": "", "templateType": "anything", "group": "Ungrouped variables", "definition": "if(q=m,0.5,-0.5)"}, "s3": {"name": "s3", "description": "", "templateType": "anything", "group": "Ungrouped variables", "definition": "if(s=5,0.5,-0.5)"}, "b21": {"name": "b21", "description": "", 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