$\"\"$

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The vector $\"\"$ .

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The magnitude of vector $\"\"$ is $\"\"$ .

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The angle between $\"\"$ and $\"\"$ is $\"\"$ .

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Let $\"\"$ .

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The angle between $\"\"$ and $\"\"$ is $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$

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The magnitude of vector $\"\"$ is $\"\"$ .

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$\"\"$

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Squaring on each side.

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$\"\"$

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$\"\"$

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Substitute $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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Solve for $\"\"$ .

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The roots of $\"\"$ are $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ and $\"\"$ .

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$\"\"$ and $\"\"$ .

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$\"\"$

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Find $\"\"$ when $\"\"$ .

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Substitute $\"\"$ in $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$ .

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Find $\"\"$ when $\"\"$ .

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Substitute $\"\"$ in $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$ .

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Vector $\"\"$ or $\"\"$ .

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$\"\"$

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$\"\"$ or $\"\"$ .