Trigonometric Identities Question 202
Question: If $ {{\sin }^{2}}\theta =\frac{x^{2}+y^{2}+1}{2x} $ , then x must be
[UPSEAT 2004]
Options:
A) - 3
B) - 2
C) 1
D) None of these
Show Answer
Answer:
Correct Answer: D
Solution:
$ {{\sin }^{2}}\theta \le 1 $ \ $ \frac{x^{2}+y^{2}+1}{2x}\le 1 $ $ x^{2}+y^{2}-2x+1\le 0 $ . $ {{(x-1)}^{2}}+y^{2}\le 0 $ It is possible, iff $ x=1 $ and $ y=0 $ , i.e., It also depends on value of y. Hence, option (d) is correct.
BETA
