Advertisements
Advertisements
Question
Which of the following is correct?
Options
(a – b)2 = a2 + 2ab – b2
(a – b)2 = a2 – 2ab + b2
(a – b)2 = a2 – b2
(a + b)2 = a2 + 2ab – b2
Advertisements
Solution
(a – b)2 = a2 – 2ab + b2
Explanation:
We have,
(a – b)2 = (a – b)(a – b)
= a(a – b) – b(a – b)
= a · a – a · b – b · a + b · b
= a2 – ab – ab + b2 ...[∵ a · b = b · a]
= a2 – 2ab + b2
And (a + b)2 = (a + b)(a + b)
= a · a + a · b + b · a + b · b
= a2 + 2ab + b2
APPEARS IN
RELATED QUESTIONS
Factorize: a (a + b)3 - 3a2b (a + b)
Factorize x2 - y2 - 4xz + 4z2
Factorize `x^2 - sqrt3x - 6`
Factorize `21x^2 - 2x + 1/21`
Multiply: x2 + 4y2 + z3 + 2xy + xz − 2yz by x − 2y − z
Write the value of 253 − 753 + 503.
Divide: 8x + 24 by 4
Divide: 10a3 - 15a2b by - 5a2
Divide: 6x3 + 5x2 − 21x + 10 by 3x − 2
The largest number of the three consecutive numbers is x + 1, then the smallest number is ________
