JEE PYQ: Functions Question 39
Question 39 - 2019 (12 Jan Shift 2)
Considering only the principal values of inverse functions, the set $A = \left{x \ge 0 : \tan^{-1}(2x) + \tan^{-1}(3x) = \frac{\pi}{4}\right}$:
(1) contains two elements
(2) contains more than two elements
(3) is a singleton
(4) is an empty set
Type: MCQ
Show Answer
Answer: (3) is a singleton
Solution
$6x^2 + 5x - 1 = 0 \Rightarrow x = \frac{1}{6}$ (as $x \ge 0$)
$A$ is a singleton set.
BETA
