解题思路:由a+b+c=0得,(a+1)+(b+2)+(c+3)=6,两边平方得(a+1)2+(b+2)2+(c+3)2+2(a+1)(b+2)+2(a+1)(c+3)+2(b+2)(c+3)=36,再由
1
a+1
+
1
b+2
+
1
c+3
=0
去分母,得(b+2)(c+3)+(a+1)(c+3)+(a+1)(b+2)=0,代入上式即可.
∵a+b+c=0,∴(a+1)+(b+2)+(c+3)=6,两边平方得(a+1)2+(b+2)2+(c+3)2+2[(a+1)(b+2)+(a+1)(c+3)+(b+2)(c+3)]=36,又由1a+1+1b+2+1c+3=0去分母,得(b+2)(c+3)+(a+1)(c+3)+(a+1)(b...
点评:
本题考点: 分式的混合运算.
考点点评: 本题考查了分式的混合运算.关键是将已知等式变形,得出与所求结果相同的结构,采用两边平方的方法求解.