判别式的应用技巧

The Application Skills of Discriminant

一元二次方程的判别式除了应用于判断一元二次方程的根的情况之外,在不等式、函数、平面几何、解析几何等方面均有重要应用.本文略举几例,以说明判别式的应用技巧.

The disciminant of quadratic equation is one of the important contents in one variable. Besides applied to judging the root of quadratc equation in one variable, it can also be applied to inequality, function, planimetry, and analytic geometry. This thesis will give some examples to illustrate the application skills of discriminant.