MCQ
The angle made by the vector $\left( {\hat i\,\, + \;\,\hat j} \right)$ with $x-$ axis and $y$ axis is
- A$45^o, 60^o$
- B$60^o, 60^o$
- ✓$45^o, 45^o$
- D$60^o, 45^o$
✓
Answer
Correct option: C.
$45^o, 45^o$
c
$a = \sqrt {{a_x}^2\,\, + \;\,{a_y}^2} = \sqrt {{1^2} + \;\,{1^2}} = \sqrt 2$
$a = \sqrt {{a_x}^2\,\, + \;\,{a_y}^2} = \sqrt {{1^2} + \;\,{1^2}} = \sqrt 2$
$\cos \alpha = \frac{{{a_x}}}{a} = \frac{1}{{\sqrt 2 }}$
$\therefore \alpha = 45^\circ ;\,\cos \,\beta = \frac{{{a_y}}}{a} = \frac{1}{{\sqrt 2 }}$
$\therefore \beta = 45^\circ $
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