Question

What is the value of f(x) when x = 4 in the piecewise function f(x) = 2x² when x>4

4x when x < 4

Answer 1

16

Explanation:

f(x) = 2x² when x>4

We cannot use this expression of f to calculate f(4)

because ,this expression define f for the value of x

that are greater (not equal) than 4.

………………………………………………………

f(x) = 4x when x ≤ 4 , here x is can be equal to 4

(notice the sign ≤ )

Therefore

f(4) = 4 × (4) = 16