MCQ
The component of vector $A = 2\hat i + 3\hat j$ along the vector $\hat i + \hat j$is
- ✓$\frac{5}{{\sqrt 2 }}$
- B$10\sqrt 2 $
- C$5\sqrt 2 $
- D$5$
✓
Answer
Correct option: A.
$\frac{5}{{\sqrt 2 }}$
a
(a)$\frac{{\overrightarrow A .\overrightarrow B }}{{|\vec i + \vec j|}} = \frac{{(2\hat i + 3\hat j)\,(\hat i + \hat j)}}{{\sqrt 2 }}$$ = \frac{{2 + 3}}{{\sqrt 2 }} = \frac{5}{{\sqrt 2 }}$
(a)$\frac{{\overrightarrow A .\overrightarrow B }}{{|\vec i + \vec j|}} = \frac{{(2\hat i + 3\hat j)\,(\hat i + \hat j)}}{{\sqrt 2 }}$$ = \frac{{2 + 3}}{{\sqrt 2 }} = \frac{5}{{\sqrt 2 }}$
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