运算能力是高考重点考查的能力之一,消元可以减少未知数或变量的个数,起到化繁为简之效,因而在数学运算中发挥着重要的作用.一、消元的作用消元一般存在于表达式、方程、不等式的变形中,是揭示数学问题隐含于表达式、 Computational ability is one of the key examinations ability of the college entrance examination, elimination can reduce the number of unknowns or variables, played a complex and effective, and thus play an important role in mathematical operations. Generally exist in the expression, equation, inequality of the deformation, is to reveal the mathematical problems implied in the expression,