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Question
The formula `(vec"a" + vec"b")^2 = vec"a"^2 + vec"b"^2 + 2vec"a" xx vec"b"` is valid for non-zero vectors `vec"a"` and `vec"b"`
Options
True
False
Solution
This statement is False.
Explanation:
`(vec"a" + vec"b")^2 = (vec"a" + vec"b") * (vec"a" + vec"b")`
= `|vec"a"|^2 + |vec"b"|^2 + 2vec"a" * vec"b"`
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