∵a+b+c=0，∴a+b=-c，∴（a+b）2=a2+2ab+b2=c2，∴c2-a2-b2=2ab，∴a2÷bc+b2÷ac+c2÷ab=（a3+b3+c3）÷abc，=[（a+b）（a2-ab+b2）+c3]÷abc，=[c3-c（a2+b2-ab）]÷abc，=c（c2-a2-b2+ab）÷abc，=3abc÷abc，=3...