$\"\"$

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The vectors are $\"\"$ and $\"\"$ .

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

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Consider $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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Substitute $\"\"$ , $\"\"$ and $\"\"$ in $\"\"$ .

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$\"\"$

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$\"\"$

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The angle between the two vectors is $\"\"$ .