If A → and B → are two vectors satisfying the relation A → · B → = | A →…

If A→ and B→ are two vectors satisfying the relation A→·B→=|A→×B→|. Then the value of |A→-B→| will be:
  1. A2+B2
  2. A2+B2+2AB
  3. A2+B2+2AB
  4. A2+B2-2AB

Solution

A→·B→=|A→×B→|
ABcosθ=ABsinθ⇒θ=45°
|A→-B→|=A2+B2-2ABcos45°
=A2+B2-2AB
Hence option (4).

Asked in: JEE Main 2021 (20 Jul Shift 1)

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