Because (1, 0), (3,2) does not belong to E.

(2, 1) belongs to e.

conditional

6 & gt=(2-a)^2+3b

( 1-a)^2+3b>； 0

(3-a)^2+3b>； 12

That is, (1.2, 1.3 added) (square difference formula)

a & lt-0.5

a & gt- 1.5

That is a=- 1 b=- 1.

Method 2:

Set e represents the part above the parabola y = (x-a) 2/6+0.5b and above the parabola.

Point A(2, 1) B( 1, 0) c (3,2) is on the straight line Y = X- 1

Point A belongs to set E, and points B and C do not belong to set E, that is,

1. Parabola and straight line intersect (2, 1).

Get a = b =- 1.

2. A parabola and a straight line have two intersections, M(x 1, y 1) and N(x2, y2), and 1

No answer

From this we can get: a = b =- 1