The signs of and for a twice-differentiable function are shown below
MATHEMATICS · Single correct · A Level · Mathematics · Differentiation · Differentiation
Problem
The signs of g′(x) and g′′(x) for a twice-differentiable function g are shown below.
Interval (−∞,−1)(−1,2)(2,∞)g′(x) \;–\; \;+\; \;+\;
g′′(x) \;–\; \;–\; \;+\;
On which interval is g decreasing and concave down?
(a) (−1,2)
(b) (−∞,2)
(c) (−∞,−1)
(d) (−1,∞)