defence exam Coast Guard Navik GD (General Duty) 02/2025 Mock Test Series Mathematics Differential Calculus Applications of Derivatives
For which interval the given function f(x) = -2x3 - 9x2 - 12x + 1 is decreasing
1
(-2, ∞)
2
(-2, -1)
3
(-∞, -1)
4
(-∞, -2) ∪ (-1, ∞)