Question

If f(x) = 2x2 + 1, what is f(x) when x = 3?

Answer 1

2(3)^2 +1
2 (3*3)+1
2(9)+1
18+1
19.

Answer 2

The answer is 19

Just replace x = 3

 f(3) = 2x2 + 1

 f(3) = 2(3^2) + 1

 f(3) = 2(9) + 1

 f(3) = 18 + 1

 f(3) = 19