Question
Show that the function f (x) = x7 + 8 x5 + 1 is increasing function for all values of x.
Solution
Here f (x) = x7 + 8 x5 + 1
∴ f ' (x) = 7x6 + 40 x4 ≥ 0 ∀ x
∴ f (x) is increasing function for all values of x.
