Question

 The square of an odd number is always odd

Try Examples with three odd numbers to check this conjecture And find where it’s false

Do you believe it’s true or false

Explain why it’s true or false

Answer 1

Answer:

True

Step-by-step explanation:

3² = 9  ⇒ odd

7² = 49 ⇒ odd

9² = 81 ⇒ odd

Therefore, the square of an odd number is always odd.

Proof

If n is an odd number, it can be written as n = 2k + 1, for some integer k.

Therefore, n² = (2k + 1)²

                      = 4k² + 4k + 1

                      = 2(2k² + 2k) + 1

As 2(2k² + 2k) + 1 is odd, this proves that the square of an odd number is always odd.