The graph of which function has an axis of symmetry at x = - 1/4?

f (x) = 2x2 + x - 1

f (x) = 2x2 - x + 1

f (x) = x2 + 2x - 1

f (x) = x2 - 2x + 1

F (x) = 2x^2 + x - 1 written in vertex form is 2 (x^2 + 1/2x - 1/2) = 2 (x^2 + 1/2x + 1/16 - 1/2 - 1/16) = 2 (x^2 + 1/2x + 1/16) - 2 (9/16) = 2 (x + 1/4) - 9/8

Axis of symmetrry is at x = 1/4

f (x) = 2x^2 - x + 1 written in vertex form is 2 (x^2 - 1/2x + 1/2) = 2 (x^2 - 1/2x + 1/16 + 1/2 - 1/16) = 2 (x^2 - 1/2x + 1/16) + 2 (7/16) = 2 (x - 1/4) + 7/8

Axis of symmetry is at x = - 4.

Therefore, the correct answer is the second option.