Rohan says: 'If I take any odd number greater than 1, say 2k+1, then (2k+1)^2 = 4k(k+1) + 1, which is always one more than a multiple of 8.' Using this, what is the remainder when 15^2 is divided by 8?

Question

Accepted Answer

1. The square of any odd number leaves remainder 1 on division by 8. 15^2 = 225 = 8 x 28 + 1, remainder 1.

Rohan says: 'If I take any odd number greater than 1, say $2 k + 1$ , then $(2 k + 1)^{2} = 4 k (k + 1) + 1$ , which is always one more than a multiple of 8.'
Using this, what is the remainder when $1 5^{2}$ is divided by 8?

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More Class 8 Properties of Square Numbers practice

Rohan says: 'If I take any odd number greater than 1, say 2k+1, then (2k+1)2=4k(k+1)+1, which is always one more than a multiple of 8.'Using this, what is the remainder when 152 is divided by 8?

Step-by-Step Solution

Master this chapter in 30 minutes a day.

More Class 8 Properties of Square Numbers practice

Rohan says: 'If I take any odd number greater than 1, say $2 k + 1$ , then $(2 k + 1)^{2} = 4 k (k + 1) + 1$ , which is always one more than a multiple of 8.'
Using this, what is the remainder when $1 5^{2}$ is divided by 8?