Trigonometric Equations Question 73
Question: If $ r,\sin \theta =3,r=4(1+\sin \theta ),0\le \theta \le 2\pi , $ then $ \theta = $
[Roorkee 1974]
Options:
A) $ \frac{\pi }{6},\frac{\pi }{3} $
B) $ \frac{\pi }{6},\frac{5\pi }{6} $
C) $ \frac{\pi }{3},\frac{\pi }{4} $
D) $ \frac{\pi }{2},\pi $
Show Answer
Answer:
Correct Answer: B
Solution:
- Eliminating $ r $ , we get
$ \therefore $ $ \sin \theta =\frac{1}{2},,-\frac{3}{2} $ (rejected)
$ \Rightarrow $ $ \theta =\frac{\pi }{6},,\pi -\frac{\pi }{6}=\frac{5\pi }{6} $ .
BETA
