Math, asked by roshangmailcom1128, 10 months ago

For Any Positive Integer N Prove That N2-N Is Divisible By 6

Answers

Answered by jatin3621
0

Answer:

Plzzz Mark it as a brainliest

well to prove it let the number be ,for example,4

then 

4²=16

according to question 

n²-n

so

4²-4=16-4=12

now to check divisibility by 6 the last digit should be a number divisible by 2 and the sum of the numbers should be divisible by 3 

since 12 is divisible by both 2 and 3 so it is also divisible by 6

hence proved

hope it helps

Plzz mark it as a brainliest♥♥♥♥♥♥

Step-by-step explanation:

Answered by siddiquizeba292
1

Answer:

n3 - n = n (n2 - 1) = n (n - 1) (n + 1)

Whenever a number is divided by 3, the remainder obtained is either 0 or 1 or 2.

∴ n = 3p or 3p + 1 or 3p + 2, where p is some integer.

If n = 3p, then n is divisible by 3.

If n = 3p + 1, then n – 1 = 3p + 1 –1 = 3p is divisible by 3.

If n = 3p + 2, then n + 1 = 3p + 2 + 1 = 3p + 3 = 3(p + 1) is divisible by 3.

So, we can say that one of the numbers among n, n – 1 and n + 1 is always divisible by 3.

⇒ n (n – 1) (n + 1) is divisible by 3.

Similarly, whenever a number is divided 2, the remainder obtained is 0 or 1.

∴ n = 2q or 2q + 1, where q is some integer.

If n = 2q, then n is divisible by 2.

If n = 2q + 1, then n – 1 = 2q + 1 – 1 = 2q is divisible by 2 and n + 1 = 2q + 1 + 1 = 2q + 2 = 2 (q + 1) is divisible by 2.

So, we can say that one of the numbers among n, n – 1 and n + 1 is always divisible by 2.

⇒ n (n – 1) (n + 1) is divisible by 2.

Since, n (n – 1) (n + 1) is divisible by 2 and 3.

∴ n (n-1) (n+1) = n3 - n is divisible by 6.( If a number is divisible by both 2 and 3 , then it is divisible by 6)

I hope it is helpful to you

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