(5x²-2)²-[3(x+3)]²=0[(5x²-2)+3(x+3)][(5x²-2)²-3(x+3)]=0(5x²+3x+7)(5x²-3x-11)=05x²+3x+7=0无解所以5x²-3x-11=0x=(3±√229)/10