1
Question
Expand the following:
(1) (x − y)2
(2) (x − 4)2
(3) (2n − 5)2
(4) (7 − 4m)2
(5) (5y −9)2
(6) (2a − 3b)2
(1) (x − y)2
(2) (x − 4)2
(3) (2n − 5)2
(4) (7 − 4m)2
(5) (5y −9)2
(6) (2a − 3b)2
Open in App
Solution
(1) (x − y)2
The given expression is of the form (a − b)2 .
Thus, we can use the identity (a − b)2 = a2 − 2ab + b2 .
∴ (x − y)2 = x2 − 2xy + y2
(2) (x − 4)2
The given expression is of the form (a − b)2 .
Thus, we can use the identity (a − b)2 = a2 − 2ab + b2 .
∴ (x − 4)2 = (x)2 − 2 (x) (4) + (4)2
= x2 − 8x + 16
(3) (2n − 5)2
The given expression is of the form (a − b)2 .
Thus, we can use the identity (a − b)2 = a2 − 2ab + b2 .
∴ (2n − 5)2 = (2n)2 − 2 (2n) (5) + (5)2
= 4n2 − 20n + 25
(4) (7 − 4m)2
The given expression is of the form (a − b)2 .
Thus, we can use the identity (a − b)2 = a2 − 2ab + b2 .
∴ (7 − 4m)2 = (7)2 − 2 (7) (4m) + (4m)2
= 49 − 56m + 16m2
(5) (5y − 9)2
The given expression is of the form (a − b)2 .
Thus, we can use the identity (a − b)2 = a2 − 2ab + b2 .
∴ (5y − 9)2 = (5y)2 − 2 (5y) (9) + (9)2
= 25y2 − 90y + 81
(6) (2a − 3b)2
The given expression is of the form (a − b)2 .
Thus, we can use the identity (a − b)2 = a2 − 2ab + b2 .
∴ (2a − 3b)2 = (2a)2 − 2 (2a) (3b) + (3b)2
= 4a2 − 12ab + 9b2
The given expression is of the form (a − b)2 .
Thus, we can use the identity (a − b)2 = a2 − 2ab + b2 .
∴ (x − y)2 = x2 − 2xy + y2
(2) (x − 4)2
The given expression is of the form (a − b)2 .
Thus, we can use the identity (a − b)2 = a2 − 2ab + b2 .
∴ (x − 4)2 = (x)2 − 2 (x) (4) + (4)2
= x2 − 8x + 16
(3) (2n − 5)2
The given expression is of the form (a − b)2 .
Thus, we can use the identity (a − b)2 = a2 − 2ab + b2 .
∴ (2n − 5)2 = (2n)2 − 2 (2n) (5) + (5)2
= 4n2 − 20n + 25
(4) (7 − 4m)2
The given expression is of the form (a − b)2 .
Thus, we can use the identity (a − b)2 = a2 − 2ab + b2 .
∴ (7 − 4m)2 = (7)2 − 2 (7) (4m) + (4m)2
= 49 − 56m + 16m2
(5) (5y − 9)2
The given expression is of the form (a − b)2 .
Thus, we can use the identity (a − b)2 = a2 − 2ab + b2 .
∴ (5y − 9)2 = (5y)2 − 2 (5y) (9) + (9)2
= 25y2 − 90y + 81
(6) (2a − 3b)2
The given expression is of the form (a − b)2 .
Thus, we can use the identity (a − b)2 = a2 − 2ab + b2 .
∴ (2a − 3b)2 = (2a)2 − 2 (2a) (3b) + (3b)2
= 4a2 − 12ab + 9b2
Suggest Corrections
0
Similar questions
View More
Join BYJU'S Learning Program
Explore more
Join BYJU'S Learning Program
