1) [–1, 1] 2) (–∞, 1) 3) [1, +∞) 4) None of these Solution: (2) (–∞, 1) f (x) = x4 – 4x For f (x) to be decreasing, f’ (x) < 0... View Article
1) (–∞, 0] 2) [0, ∞) 3) R 4) None of these Solution: (3) R Since f’ (x) = 3 / [x + 1]2 is greater than 0 in interval (- ∞, ∞),... View Article