To find f(x) when x = 3, we need to substitute 3 into the function f(x) = 2x² + 1.
First, we calculate x²:
3² = 9
Next, we multiply this result by 2:
2 * 9 = 18
Finally, we add 1 to this value:
18 + 1 = 19
So, f(3) = 19.
In conclusion, when x is 3, the value of f(x) is 19.