解:(x—3)2+x2—9=0 (x—3)2+(x+3)(x—3)=0 (x—3)[(x—3)+(x+3)]=0 即:2x(x—3)=0 2x=0或x—3=0 x1=0 x2=3
(x-3)²+x²=9x²-6x+9+x²=92x²-6x=02x(x-3)=0x(x-3)=0x=0或x=3
(x-3)²+x²=9(x-3)²=9-X²x-3=-3-xx=0