(X十2)^2-4(X一3)^2=O解:X^2+4X十4一4(X^2-6X十9)=0X^2十4X十4一4X^2+24X一36=0一3X^2+28X一32=O3X^2-28X十32=0(3X一4)(X一8)=0X1=4/3,X2=8