Prove that: 2a2+2b2+2c2-2ab-2bc-2ca=a-b2+b-c2+c-a2

Prove that: $2 a^{2} + 2 b^{2} + 2 c^{2} - 2 a b - 2 b c - 2 c a = [{(a - b)}^{2} + {(b - c)}^{2} + {(c - a)}^{2}]$

Match the items on the right to the items on the left.

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