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$\\boldsymbol{(A\\cdot B)\\cdot C}$

", "

$\\boldsymbol{(A\\cdot B)C}$

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$\\boldsymbol{(A\\cdot B)\\times C}$

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$\\boldsymbol{(A\\times B)\\times C}$

", "

$\\boldsymbol{(A\\times B)\\cdot C}$

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Scalar

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Vector

", "

Undefined

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Given the vectors $\\boldsymbol{A},\\;\\;\\boldsymbol{B}$ and $\\boldsymbol{C}$ in $3$ dimensional space, state whether the following quantities are scalars, vectors or undefined.

", "tags": ["checked2015", "cross product", "dot product", "inner product", "mas1602", "MAS2104", "scalar product", "scalars", "unused", "vector", "Vector", "vector product", "vectors"], "rulesets": {"std": ["all", "fractionNumbers", "!collectNumbers", "!noLeadingMinus"]}, "preamble": {"css": "", "js": ""}, "type": "question", "metadata": {"notes": "\n \t\t

15/07/2012:

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Added tags.

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16/07/2012:

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Added tags.

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Determine if various combinations of vectors are defined or not.

"}, "advice": "\n \n \n

1. $\\boldsymbol{(A\\cdot B)\\cdot C}$ is undefined as $\\boldsymbol{A\\cdot B}$ is a scalar and we cannot take the inner product of a scalar with the vector $\\boldsymbol{C}$.

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2. $\\boldsymbol{(A\\cdot B)C}$ is a vector and is a multiple of $\\boldsymbol{C}$ as $\\boldsymbol{A \\cdot B}$ is a scalar.

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3. $\\boldsymbol{(A\\cdot B)\\times C}$ is undefined as $\\boldsymbol{A\\cdot B}$ is a scalar and the cross product is only defined between vectors.

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4. $\\boldsymbol{(A\\times B)\\times C}$ is a vector as $\\boldsymbol{A \\times B}$ and $\\boldsymbol{C}$ are vectors and the cross product between vectors produces a vector.

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5. $\\boldsymbol{(A\\times B)\\cdot C}$ is a scalar as $\\boldsymbol{A \\times B}$ and $\\boldsymbol{C}$ are vectors and the inner or dot product is between vectors and produces a scalar.

\n \n \n ", "contributors": [{"name": "Newcastle University Mathematics and Statistics", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/697/"}]}]}], "contributors": [{"name": "Newcastle University Mathematics and Statistics", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/697/"}]}