Advertisements
Advertisements
Question
The value of (a + b)2 – (a – b)2 is ______.
Options
4ab
– 4ab
2a2 + 2b2
2a2 – 2b2
Solution
The value of (a + b)2 – (a – b)2 is 4ab.
Explanation:
We have,
(a + b)2 – (a – b)2 = a2 + b2 + 2ab – (a2 + b2 – 2ab) ...[∵ (a + b)2 = a2 + b2 + 2ab and (a – b)2 = a2 + b2 – 2ab]
= a2 + b2 + 2ab – a2 – b2 + 2ab
= a2 – a2 + b2 – b2 + 2ab + 2ab
= 2ab + 2ab ...[Combining the like terms]
= 4ab
APPEARS IN
RELATED QUESTIONS
Write numerical co-efficient of the following: y
Find the sum of: a2 + b2 + 2ab, 2b2 + c2 + 2bc and 4c2 -a2 + 2ac
Simplify: p + q – (p – q) + (2p – 3q)
Simplify: 6a – 3 (a + b – 2)
Coefficient of y in the term `(-y)/3` is ______.
(9x – 51) ÷ 9 is x – 51.
Factorise the following expression.
a3 + a2 + a + 1
Factorise the following expression.
a3x – x4 + a2x2 – ax3
Identify term and factor in the expression given below:
5y + 3y2
Identify term and factor in the expression given below:
`3/4 x + 1/4`