Trigonometric Identities Question 51
Question: $ \frac{\cos 12{}^\circ -\sin 12{}^\circ }{\cos 12{}^\circ +\sin 12{}^\circ }+\frac{\sin 147{}^\circ }{\cos 147{}^\circ }= $
[MP PET 1991]
Options:
A) 1
B) -1
C) 0
D) None of these
Show Answer
Answer:
Correct Answer: C
Solution:
$ \frac{\cos ,12^{o}-\sin ,12^{o}}{\cos 12^{o}+\sin 12^{o}}+\frac{\sin 147^{o}}{\cos 147^{o}} $ $ =\frac{1-\tan 12^{o}}{1+\tan 12^{o}}+\tan 147^{o} $ $ =\tan 33^{o}-\tan 33^{o}=0 $ .