Question 84 (iii)
Simplify
(79a+97b)2−ab
We have, (79a+97b)2−ab =(79a)2+(97b)2+2×79a×97b−ab [using the identity, (a+b)2=a2+b2+2ab] =4981a2+8149b2+2ab−ab=4981a2+ab+8149b2
Question 84 (ix)
(a−b)(a2+b2+ab)−(a+b)(a2+b2−ab)
Simplify :
(ab−c)2+2abc
Question 84 (viii)