MATHS DIFF. CAL. (MOCK PH. TEST) MAINS PATTERN ⎛ + y 2x − ⎞ 1. If f ⎜ 2x , y ⎟ = xy, then f(x, y) + f (y, x) = 8 8 ⎝ ⎠ (A) 1 (B) 0 (C) 2 (D) 3 2. The domain of definition of f(x) = sec -1 (cos 2 x) is (A) m π , m ∈ I (B) π /2 (C) π /4 (D) none of these 3. If f : R → R is the function defined by f(x) = e x 2 − e − x 2 , then e x 2 + e − x 2 (A) f(x) is an increasing function (B) f(x) is a decreasing function (C) f(x) is onto (D) none of these. 4. The function f(x) = 1 + sin x − cos x is not defined at x = 0. The value of f(0) so that 1 − sin x − cos x f(x) is continuous at x = 0,...