Question

In the interval (–3, 3) the function f(x) = x/3 + 3/x; x ¹ 0 is

• A. Increases
• B. Decreases
• C. Neither increases nor decreases
• D. Partly increases and partly decrease

Answer 1

Answer: (B)

Decreases

Answer 2

f(x) = $\frac{x}{3} + \frac{3}{x}$ , f'(x) = $\frac{1}{2} - \frac{3}{x^{2}}$ = $\frac{x^{2} - 9}{3x^{2}}$

In x Ī (–3, 3) f '(n) < 0 \ it is decreases function