Functions Question 646
Question: The range of $ f(x)=\cos 2x-\sin 2x $ contains the set
[IIT Screening]
Options:
A) [2, 4]
B) [?1, 1]
C) [?2, 2]
D) [?4, 4]
Show Answer
Answer:
Correct Answer: B
Solution:
$ f(x)=\sqrt{2},[ \sin ( \frac{\pi }{4}-2x ) ] $
$ \therefore -\sqrt{2}\le f(x)\le \sqrt{2} $ and $ [-1,1],\subset ,[-\sqrt{2},\sqrt{2}] $ .
BETA
