1, when the distance between the center of the coin and each side of the square is greater than 1cm, there is no common intersection between the coin and the grid, that is, when the center of the coin falls in a square with a side length of 4cm, there is no common intersection between the coin and the grid, so the probability of common intersection is: 1-4 2.

2.( 1) With A as the abscissa and B as the ordinate, the values of A and B are respectively (1, 1), (-1, 1), (1,/kloc-0. If two of +ax+b = 0 are real numbers, then a? The point of -4b ≥ 0 is a parabola b = 1/4a? The area enclosed by the square below can be calculated as 13/6 through integration, so the probability is 13/6 ÷ 4 = 13/24.

(2) imitate the above. At this time, A and B should not only satisfy A, right? -4b ≥ 0, and a < 0, b > 0 must be satisfied, so that a and b that meet the conditions fall on the parabola b = 1/4a? In the second quadrant, the lower area surrounded by the X axis and the straight line X =- 1 can be obtained as 1/6 through integration, so the probability is 1/6 ÷ 4 = 1/24.