Trigonometric Equations Question 376
Question: The solution of the equation $ 4{{\cos }^{2}}x+6 $ $ {{\sin }^{2}}x=5 $
[AI CBSE 1983]
Options:
A) $ x=n\pi \pm \frac{\pi }{2} $
B) $ x=n\pi \pm \frac{\pi }{4} $
C) $ x=n\pi \pm \frac{3\pi }{2} $
D) None of these
Show Answer
Answer:
Correct Answer: B
Solution:
- $ 4+2{{\sin }^{2}}x=5 $
$ \Rightarrow $ $ {{\sin }^{2}}x=\frac{1}{2}={{\sin }^{2}}\frac{\pi }{4}\Rightarrow x=n\pi \pm \frac{\pi }{4} $ .
BETA
