Question

The function f is defined by f(x) = (x + 2)e–x is

(a) decreasing for all x

(b) decreasing in (– ∞, – 1) and increasing in (– 1, ∞)

(c) increasing for all x.

(d) decreasing in (– 1, ∞) and increasing in (–∞, – 1)

Answer 1

Correct option (d) decreasing in (– 1, ∞) and increasing in (–∞, – 1)

Explanation:

Thus, f(x) increasing in (–∞, – 1) and decreasing in (– 1, ∞).