As shown in the figure, the graph of the function f (x) defined on [- 1, + ∞) consists of a line segment and a part of a parabola, then the analytic expression of F (x) is______ .

As shown in the figure, the graph of the function f (x) defined on [- 1, + ∞) consists of a line segment and a part of a parabola, then the analytic expression of F (x) is______ .

When x ∈ [- 1, 0], let y = KX + B, get − K + B = 0k × 0 + B = 1 from the image, get k = 1b = 1, | y = x + 1; when x > 0, let y = a (X-2) 2-1, get 0 = a (4-2) 2-1 from the image, get a = 14, | y = 14 (X-2) 2-1 from the image, we can see that f (x) = x + 1, X ∈ [- 1, 0] 14 (x − 2) 2 − 1, X ∈ (0, + ∞)