错觉是指人们对外界事物的不正确的感觉或知觉.最常见的是视觉方面的错觉.产生错觉的原因,除来自客观刺激本身特点的影响外,还有观察者生理上和心理上的原因.在初中学生解决几何问题的时候,经常出现因所给的图形本身的一些特点而导致感觉先入为主,不能客观地分析已知条件和未知条件,造成失误.近年也出现了易使学生产生错觉的中考题,出题者似 The illusion refers to people’s perception or perception of the outside world is not the most common visual illusion .In the illusion of reason, in addition to the characteristics of the objective stimuli from the impact of their own, as well as the observer physiological and psychological reasons When junior high school students solve the geometric problems, often because of the characteristics of the graphics given by some of the characteristics leading to the feeling of preconceptions, can not objectively analyze the known conditions and unknown conditions, resulting in mistakes .In recent years, there have been easy to make students illusion In the exam, a title like