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Question
The angle θ between two non-zero vectors `bar("a")` and `bar("b")` is given by cos θ = ______
Options
`(bar"a"*bar"b")/(|bar("a")||bar("b")|)`
`bar("a")*bar("b")`
`|bar("a")||bar("b")|`
`(|bar("a")||bar("b")|)/(bar("a")*bar("b"))`
Solution
`(bar"a"*bar"b")/(|bar("a")||bar("b")|)`
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