If f(x ) = 2x² + 3, find f(3).

Solution:

Given function f(x ) = 2x² + 3

f(x = 3) can be obtained as follows:

f(3) = 2(3)² + 3

= 2(9) + 3

= 18 + 3

= 21

Another example could be: If f(x) = x³ + 5x² + 6x, find f(-2)

f(-2) = (-2)³ + 5(-2)² + 6(-2)

= -8 + 5(4) - 12

= -8 + 20 - 12

= 0

If f(x ) = 2x² + 3, find f(3).

Summary:

If f(x ) = 2x² + 3, then the value of f(3) = 21