5a的二次方+2b的二次方+c的二次方-2ab+2bc-8a+4=0,求abc

问题描述:

5a的二次方+2b的二次方+c的二次方-2ab+2bc-8a+4=0,求abc

5a²+2b²+c²-2ab+2bc-8a+4=04a²-8a+4+a²-2ab+2bc+b²+b²+c²=04(a-1)²+(a-b)²+(b+c)²=0a=1b=ab=-ca=1,b=1,c=-1abc=-1