一元二次方程根的判别式主要用于判断方程根的情况,灵活运用它还可以解决其它问题.一、用于求值例1如果代数式(2m-1)x2+2(m+1)x+4是完全平方式,求m的值.解:∵代数式(2m-1)x2+2(m+1)x+4是完全平方式,∴(2m-1)x2+2(m+1)x+4=0有两个相等的实数根.∴△=〔2(m+1)〕2-4×4(2m-1)=0.解 The discriminant of the root of a quadratic equation is mainly used to judge the root of the equation. Using it flexibly can also solve other problems. One, for evaluation example 1 if algebraic expression (2m-1)x2+2(m+1)x +4 is a completely flat method, find the value of m. Solution: ∵ Algebraic formula (2m-1) x2+2(m+1)x+4 is a completely flat method, ∴(2m-1)x2+2(m+1) )x+4=0 has two equal real roots. ∴Δ=[2(m+1)]2-4×4(2m-1)=0.