Question

The axis of symmetry for the function f(x) = –2x2 + 4x + 1 is the line x = 1. Where is the vertex of the function located?

(0, 1)
(1, 3)
(1, 7)
(2, 1)

Answer 1

(1, 3)

Explanation: the vertex x-coordinate is -b/(2a) = -4/(2·-2) = 1, and f(1) = -2(1)^2 + 4(1) + 1 = 3, so the vertex is (1, 3).