|a+1/2|+b的平方=6b-9|a+1/2|+b²-6b+9=0|a+1/2|+(b-3)²=0∴a+1/2=0且b-3=0∴a=-1/2,b=3[(2a+b)^2+(2a+b)(b-2a)-6ab]÷(2b)=[(2a+b)(2a+b+b-2a)-6ab]÷(2b)=[2b(2a+b)-6ab]÷(2b)=(2a+b)-3a=b-a=3-(-1/2)=7...