圆既是轴对称图形又是中心对称图形,因此圆中有些结论要考虑图形在对称位置上的不同情况,也正因为这点,有许多题目由于考虑不全产生失误.例1如图,在10×6的网格中(每个小正方形的边长均为1个单位长),⊙A的半径为1,⊙B的半径为2,要使⊙A与静止的⊙B内切,那么⊙A由图示位置需向右平移____个单位长. Circle is both axisymmetric and centroid graphics, so some conclusions in the circle to consider the graphics in different positions symmetrical position, but also precisely because of this, there are many problems due to incomplete consideration of error. Example 1 shown in Figure 10 × 6 grid (the length of each small square is 1 unit), the radius of ⊙A is 1, the radius of ⊙B is 2, and ⊙A is to be inscribed with the stationary ⊙B, then ⊙A The position shown by the icon to the right translation ____ units long.