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There is no minimum on the left of the left intersection, and the maximum is at the intersection (2- root 7, 7-2-root 7).

Between the two intersections, Fx is a quadratic function, that is, the lower half, with only the minimum value-1.

On the right side of the right intersection, the maximum value is 3-2, and there is no minimum value.

To sum up: 7 has 7-2 largest roots.

There is no minimum

The second question is C.

It is about the transformation of 2 (x 1).

First, 2 x is shifted to the left 1, and then it is symmetric about y, and 2 (1-x) is obtained.

Move 2 x to the left 1 to get 2 (1 x).