Q: If (x + 1)/(x − 1) = a/b and (1 − y)/(1 + y) = b/a, then the value of (x − y)/(1 + xy) is
(a)2ab / (a² − b²)
(b)(a² − b²) / 2ab
(c)(a² + b²) / 2ab
(d)(a² − b²) / ab
Correct Answer: (a)
The correct answer is (b) '(a² − b²) / 2ab'. This question from the General Studies domain tests knowledge of Miscellaneous.