a+x²=2010 a=2010-x²
b+x²=2011 b=2011-x²
c+x²=2012 c=2012-x²
a-b=2010-x²-2011+x²=-1
b-c=2011-x²-2012+x²=-1
c-a=2012-x²-2010+x²=2
a/bc+b/ca+c/ab-1/a-1/b-1/c
=a²/abc+b²/abc+c²/abc-bc/abc-ac/abc-ab/abc
=(a²+b²+c²-ab-bc-ac)/abc
=(2a²+2b²+2c²-2ab-2bc-2ac)/2abc
=((a-b)²+(b-c)²+(c-a)²)/2abc
=(1+1+4)/48
=6/48
=1/8