devarshi-dt-logo

Question:

Find the square root of the following number by prime factorisation method: (i)729 (ii)400 (iii)1764 (iv)4096 (v)7744 (vi)9604 (vii)5929 (viii)9216 (ix)529 (x)8100

Solution:

(i)729
729 = 3 × 3 × 3 × 3 × 3 × 3 = 3² × 3² × 3²
∴√729 = 27

(ii)400
400 = 2 × 2 × 2 × 2 × 5 × 5 = 2² × 2² × 5²
∴√400 = 20

(iii)1764
1764 = 2 × 2 × 3 × 3 × 7 × 7 = 2² × 3² × 7²
∴√1764 = 42

(iv)4096
4096 = 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 = 2² × 2² × 2² × 2² × 2² × 2²
∴√4096 = 64

(v)7744
7744 = 2 × 2 × 2 × 2 × 11 × 11 = 2² × 2² × 11²
∴√7744 = 88

(vi)9604
9604 = 2 × 2 × 7 × 7 × 7 × 7 = 2² × 7² × 7²
∴√9604 = 98

(vii)5929
5929 = 7 × 7 × 11 × 11 = 7² × 11²
∴√5929 = 77

(viii)9216
9216 = 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 × 3 × 3 = 2² × 2² × 2² × 2² × 2² × 3²
∴√9216 = 96

(ix)529
529 = 23 × 23 = 23²
∴√529 = 23

(x)8100
8100 = 2 × 2 × 3 × 3 × 3 × 3 × 5 × 5 = 2² × 3² × 3² × 5²
∴√8100 = 90