一、对概念的内涵、外延理解不够透彻,导致低级失误任何一个概念、定义都有其确定的内涵、外延,应透彻理解和准确把握它们,不得随意地扩大与缩小,否则就会出错. 例如,求到两定点A(-1,0)、B(1,0)距离之和等于2的点的轨迹.很多学生会不假思索地断定“轨迹是以A、B为焦点,长半轴长为1的椭圆”.这 First, the concept of connotation, denotation is not thorough enough, resulting in low-level mistakes any concept, definition has its own connotation, extension, should be thoroughly understood and accurately grasp them, can not be arbitrarily expanded and reduced, otherwise they will make mistakes. Find the trajectory of the point where the sum of the two fixed points A(-1,0) and B(1,0) is equal to 2. Many students will conclusively conclude that “the trajectory is focused on A and B, and the long half axis length is 1. The ellipse”. This