有些数学题,由常规思路不易奏效,可破规另辟蹊径:“强攻”不成,就“智取”;正面不通, 就从侧面和反面突破;直接不行,就间接进取．在解数学题的过程中,若能及时改变视角,往往能出奇制胜,巧妙求解． 1．正难则反例1 若三个二次函数 y=x2+2mx+m2-m, Some mathematics questions, from conventional thinking, are not easy to work, but they can break new grounds: If “strength attack” fails, then “intelligence” will be adopted; if it is unreasonable, it will break through from the side and the opposite side; if it does not work directly, it will be indirect. In the process of solving mathematics problems, if you can change the perspective in time, you can often surprise and win. 1. If it is difficult, then counterexample 1 if the three quadratic functions y=x2+2mx+m2-m,