(03.06)
Using the completing the square method, rewrite f(x) = x2 + 4x - 1 in vertex form,
f(x) = (x + 2)2 + 1
Oь
f(x) - (x + 2)2
oc
f(x) = (x + 2)2 + 4
Od
f(x) = (x + 2)2 - 5