Question

Find the sum of:
(vi) $a^2+b^2+2ab,2b^2+c^2+2bc$ and $4c^2-a^2+2ac$

Answer 1

Step: Find the sum of given expressions
We need to find sum of $(a^2+b^2+2ab),(2b^2+c^2+2bc)$ and $(4c^2-a^2+2ac)$ $=(a^2+b^2+2ab)+(2b^2+c^2+2bc)+(4c^2-a^2+2ac)$ $=(a^2-a^2)+(b^2+2b^2)+(c^2+4c^2)+2ab+2bc+2ac$ [Grouping like terms]
$=0+3b^2+5c^2+2ab+2bc+2ac$ $=3b^2+5c^2+2ab+2bc+2ac$
Hence, the answer is $3b^2+5c^2+2ab+2bc+2ac.$