Evaluate the function ƒ( x ) = x 2 + 1 for ƒ(2).
If \(f(x) = x^{2} + 1\)
then \(f(2) = (2)^{2} + 1\)
∴ f(2) = (4) + 1
= 5
So in essence, whatever is the the bracket adjacent to the f, in this case 2, you substitute that for the x or x's in the equation and then solve.