Trigonometric Identities Question 86
Question: $ (\sec A+\tan A-1)(\sec A-\tan A+1)-2\tan A= $
[Roorkee 1972]
Options:
A) $ \sec A $
B) $ 2\sec A $
C) 0
D) 1
Show Answer
Answer:
Correct Answer: C
Solution:
$ (\sec A+\tan A-1)(\sec A-\tan A+1)-2\tan A $ $ =({{\sec }^{2}}A-{{\tan }^{2}}A)+\sec A+\tan A-\sec A $ $ +\tan A-1-2\tan A=0 $ $ (\because {{\sec }^{2}}A-{{\tan }^{2}}A=1) $
BETA
