Question

Question is in the attachment box.

Please find this answer because this one is the correct answer for that question so please find the process to reach this answer:

$\frac{1}{4} a {}^{2} + \: \frac{1}{4} b {}^{2} + \: \frac{1}{4} c {}^{2} + \: \frac{1}{2} ab \: + \: \frac{1}{2} bc \: + \: \frac{1}{2} ac$
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Answer 1

Answer:

use the identity (a+b+c)²=a²+b²+c²+2ab+2bc+2ac