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Question
The angle between A = `hati` + `hatj` and B = `hati` − `hatj` is ______.
Options
45°
90°
– 45°
180°
Solution
The angle between A = `hati` + `hatj` and B = `hati` − `hatj` is 90°.
Explanation:
Since we know that, the angle between two vectors is given by
⇒ `cos theta = (vecA * vecB)/(|A||B|)`
Hence, ⇒ `cos theta = (1 - 1)/(sqrt(2) * sqrt(2)) = 0/2` = 0
i.e. ⇒ θ = 90°.
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