a=(1/2014)x+2011,b=(1/2014)x+2010,c=(1/2014)x+2012,求代数式a2+b2+c2-ab-ac-bc的值

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a=(1/2014)x+2011,b=(1/2014)x+2010,c=(1/2014)x+2012,求代数式a2+b2+c2-ab-ac-bc的值
a=(1/2014)x+2011,b=(1/2014)x+2010,c=(1/2014)x+2012,求代数式a2+b2+c2-ab-ac-bc的值

a=(1/2014)x+2011,b=(1/2014)x+2010,c=(1/2014)x+2012,求代数式a2+b2+c2-ab-ac-bc的值
a2+b2+c2-ab-ac-bc
= 1/2 [ (a2 -2ab +b2) + (a2 - 2ab + c2 ) + (b2 - 2bc + c2) ]
= 1/2 [ (a-b)2 + (a-c)2 + (b-c)2 ]
= 1/2 [ (1)2 + (-1)2 + (-2)2 ]
= 1/2 ( 1 + 1 + 4 )
= 3