Given the point m (COSA, Sina), in the plane region represented by the inequality system x-y-1 ≤ 0, x + Y-1 ≤ 0, then the maximum and minimum values of the distance from the point m to the line 6x-y-4 = 0 are m, n respectively, then m-2n is equal to

Given the point m (COSA, Sina), in the plane region represented by the inequality system x-y-1 ≤ 0, x + Y-1 ≤ 0, then the maximum and minimum values of the distance from the point m to the line 6x-y-4 = 0 are m, n respectively, then m-2n is equal to

The set of points m takes the origin as the center of the circle, 1 as the radius, and points (1,0) are added to the semicircle in the second and third quadrants. Obviously, the distance from the point (1,0) to the straight line 6x-y-4 = 0 is the shortest, n = (6-4) / √ (6 ^ 2 + 1 ^ 2) = 2 / √ 37, and the farthest distance to the straight line is the intersection of the vertical line passing through the origin and the circle, so m = radius + the distance from the origin to the straight line = 1 + 4 / √ 37