原方程两边同除以2可得：x²- (5/2)*x+ 1/2=0配方得：x²- (5/2)*x+ (5/4)²- (5/4)²+(1/2)=0即(x - 5/4)²=17/16那么：x - 5/4=±(√17)/4解得：x=[5+(√17)]/4或x=[5-(√17)]/4...