MCQ
If $a = 2i + 5j$ and $b = 2i - j,$ then the unit vector along $a+b$ will be
- A$\frac{{i - j}}{{\sqrt 2 }}$
- B$i + j$
- C$\sqrt 2 (i + j)$
- ✓$\frac{{i + j}}{{\sqrt 2 }}$
✓
Answer
Correct option: D.
$\frac{{i + j}}{{\sqrt 2 }}$
d
(d) $a + b = 4i + 4j,$ therefore unit vector $\frac{{4\,(i + j)}}{{\sqrt {32} }} = \frac{{i + j}}{{\sqrt 2 }}.$
(d) $a + b = 4i + 4j,$ therefore unit vector $\frac{{4\,(i + j)}}{{\sqrt {32} }} = \frac{{i + j}}{{\sqrt 2 }}.$
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