1
4 (b-c ) 2 +bc=(a-b)(c-a)+bc ,
化简:4a 2-4a(b+c)+(b+c) 2=0, 4-4
b+c
a +
(b+c) 2
a 2 =0 ,
即: (2-
b+c
a ) 2 =0 ,
∴
b+c
a =2,则
b+c
4a =
1
2 ,
故答案为:
1
2 .
1
4 (b-c ) 2 +bc=(a-b)(c-a)+bc ,
化简:4a 2-4a(b+c)+(b+c) 2=0, 4-4
b+c
a +
(b+c) 2
a 2 =0 ,
即: (2-
b+c
a ) 2 =0 ,
∴
b+c
a =2,则
b+c
4a =
1
2 ,
故答案为:
1
2 .