Trigonometric Identities Question 23
Question: $ \frac{\cos 9{}^\circ +\sin 9{}^\circ }{\cos 9{}^\circ -\sin 9{}^\circ }= $
[EAMCET 1992; Kerala (Engg.) 2005]
Options:
A) $ \tan 54{}^\circ $
B) $ \tan 36{}^\circ $
C) $ \tan 18{}^\circ $
D) None of these
Show Answer
Answer:
Correct Answer: A
Solution:
$ =\sin \theta .\sin \theta +\cos \theta .\cos \theta =1 $ $ =\tan ,( 45^{o}+9^{o} )=\tan 54^{o} $ .
BETA
