**Question :** If A∙ B= AB, then the angle between A and B is

(A) 0°

(B) 45°

(C) 90°

(D) 180°

**Answer :** option (A)

**Solution :**

with
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**Question :** If A∙ B= AB, then the angle between A and B is

(A) 0°

(B) 45°

(C) 90°

(D) 180°

**Answer :** option (A)

**Solution :**