The equation can be written:
y+2=(x+1)², from which the vertex (-1,-2) can be derived, because y=-2, x=-1 produces 0=0. The smallest value of (x+1)² is 0 when x=-1, and y=-2 is the minimum value (at the vertex). The vertex lies on the axis of symmetry x=-1.
The domain is all x but the range is [-2,∞).