MCQ
If the angle between $a $ and $ b $ be ${30^o}$, then the angle between $3 a$ and -$ 4 b$ will be ............ $^o$
- ✓$150$
- B$90$
- C$120$
- D$30$
✓
Answer
Correct option: A.
$150$
a
(a) It is obvious from figure.
(a) It is obvious from figure.
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