NCERT Solution for Class 8 Maths Chapter – 6 SQUARE AND SQUARE ROOTS EXERCISE – 6.2
Q1. Find the square of the following numbers.
- 32
Solution:-
= ( 30 + 2 ) 2
= (30)2 + (2)2 + 2 x 30 x 2
= 900 + 4 + 120
= 1024
- (35)2
Solution:-
= ( 30 + 5 )2
= (30)2 + (5)2 + 2 x 30 x 5
= 900 + 25 + 300
= 1225
- (86)2
Solution:-
= ( 90 – 4)2
= (90)2 + (4)2 – 2 x 90 x 4
= 8100 + 16 – 720
= 8116 – 720
= 7396
- (93)2
Solution:-
= ( 90 + 3)2
= (90)2 + (3)2 + 2 x 90 x 3
= 8100 + 9 + 540
= 8649
- (71)2
Solution:-
(70 + 1 )2
(70)2 + (1)2 + 2 x 70 x 1
4900 + 1 + 140
5041
- (46)2
Solution:-
( 50 – 4 )2
(50)2 + (4)2 – 2 x 50 x 4
2500 + 16 – 400
2116
Q2. Write a Pythagorean triplet whose one number is.
- 6
Solution:-
2m = 6
M = 6/2 = 3
M2 -1 = 32 -1 = 9 – 1 = 8
M2 + 1 = 32 + 1 = 9 + 1 = 10
( 6,8,10) is a Pythagorean triplet
- 2m = 14
Solution:-
M = 14/2 = 7
M2 – 1 = 72 – 1 = 49 – 1 = 48
M2 + 1 = 72 + 1 = 49 + 1 = 50
(14 , 48 , 50) is not a Pythagorean triplet.
- 2m = 16
Solution:-
M = 16/2 = 8
M2 – 1 = 82 -1 = 64 – 1 = 63
M2 + 1 = 82 + 1 = 64 + 1 = 65
(16 , 63 , 65 ) is a Pythagorean triplet.
- 2m = 18
Solution:-
M = 18/2 = 9
M2-1 = 92 -1 = 81 -1 = 80
M2 + 1 = 92 + 1 = 81 + 1 = 82
( 18 , 80 , 82 ) is a Pythagorean triplet.
NCERT Solutions for class 7 Science Chapter -9