Question

(a-b-c)^2+(-a+b+c)^2​

Answer 1

Solution:

(a-b-c)²+(-a+b+c)²

= (a-b-c)²+[-(a-b-c)]²

= (a-b-c)²+(a-b-c)²

= 2(a-b-c)²

= 2(a²+b²+c²-2ab+2bc-2ac)

= 2a²+2b²+2c²-4ab+4bc-4ac

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