Functions Question 31
Question: $ \underset{x\to \pi /2}{\mathop{\lim }}(\sec \theta -\tan \theta )= $
[IIT 1976; AMU 1999]
Options:
A) 0
B) 1/2
C) 2
D) $ \infty $
Show Answer
Answer:
Correct Answer: A
Solution:
$ \underset{\theta \to \pi /2}{\mathop{\lim }}\frac{1-\sin \theta }{\cos \theta }=\underset{\theta \to \pi /2}{\mathop{\lim }}\frac{{{( \cos \frac{\theta }{2}-\sin \frac{\theta }{2} )}^{2}}}{( \cos \frac{\theta }{2}-\sin \frac{\theta }{2} )( \cos \frac{\theta }{2}+\sin \frac{\theta }{2} )}=0 $ .
BETA
