a)

The vectors are and .

Dot product definition:

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(b)

Find the angle between and .

Cosine of the angle between two vectors: .

Find magnitude of vector : .

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Find magnitude of vector : .

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Apply formula: .

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.

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c)

Dot product of the vectors , so the vectors are orthogonal.

The vectors are orthogonal.

a) .

b) The angle .

c) The vectors are orthogonal.