Question 65995
f(x) = 3x^2 + 6x + 1
Let y = 3x^2 + 6x + 1
      = 3(x^2 + 2x) + 1
      = 3(x^2 + 2x + 1 - 1) + 1 [completing the square]
      = 3(x^2 + 2x + 1) -3 + 1
      = 3(x+1)^2 - 2

Comparing this with the standard form, y = a(x-h)^2 + k we get,

k = -2


Good Luck!!!