Use Euclid’s division lemma to show that the square of any positive integer is either of form 3m or 3m + 1 for some integer m.
Solution:
Let ‘a’ be any positive integer and b = 3.
∴ By Euclid’s division algorithm, we have a = 3q + r, 0 ≤ r < b
a = 3q + r, 0 ≤ r < 3 [ ∵ b = 3] where q ≥ 0 and r = 0,1, 2
∴ a = 3q or 3q + 1 or 3q + 2
Now
![[Solved] Use Euclid’s division lemma to show that the square of any positive integer is either of form 3m or 3m + 1 for some integer m. 1 Use Euclid’s division lemma to show that the square of any positive integer is either of form 3m or 3m + 1 for some integer m](https://i0.wp.com/www.learninsta.com/wp-content/uploads/2020/11/NCERT-Solutions-for-Class-10-Maths-Chapter-1-Real-Numbers-Ex-1.1-6.png?w=916&ssl=1)
Thus, the square of any positive integer is either of form 3m or 3m + 1.