Question

How do you find the domain and range for `x^2 + 5x + 6`?

Answer 1

`f(x) = x^2 + 5x + 6 = (x + 2)(x + 3)`

Coordinates of vertex (minimum)

`x = -b/21 = -5/2`
`y = f(-5/2) = 25/4 - 25/2 + 6 = -1/4`

Domain for x: (-infinity, +infinity)
Range for y: (-1.4, +infinity)