aa*bb+aa+bb+1=4ab 求2a+b的值
问题描述:
aa*bb+aa+bb+1=4ab 求2a+b的值
答
aa*bb+aa+bb+1=4ab
a²b²-2ab+1+a²+b²-2ab=0
(ab-1)²+(a-b)²=0
ab-1=0
a-b=0
a=b=1或a=b=-1
2a+b=3或2a+b=-3