Question

Find the least value of f(x) = (x³ + x + 2)/x , x > 0

Answer 1

We have, f(x) = (x³ + x + 2)/x , x > 0

⇒ f(x) = x² + 2/x + 1

⇒ f(x) = (x² + 1/x + 1/x)

⇒ f(x) ≥ 3 + 1 = 4

Hence, the min value of f(x) is 4.