Question

simplify this..
hint.. ans is 4(ab+bc)

Answer 1

here's your answer
hope it helps

Answer 2

we know the formula
(a+b+c) 2 = a2 + b2 + c2 + 2ab + 2bc + 2ac

using the above formula we get

= ( a+b+c )2 - (a-b+c)2

= a2 + b2 +c2 + 2ab + 2bc + 2ac - ( a2 + b2 + c2 - 2ab - 2bc + 2ac)

= a2 + b2 + c2 +2ab + 2bc +2ac - a2 - b2 -c2 + 2ab + 2bc - 2ac

on simplyfication ( by canceling the similar terms but with different sign ( + & - ) )

we get

= 2ab + 2bc + 2ab + 2bc

= 4ab + 4bc

= 4( ab + bc)

hence simplified

hope you have understood
if you have any doubt reply me back I will solve your doubts