### Re: BdMO National Secondary: Problem Collection(2016)

Posted:

**Mon Feb 05, 2018 10:39 pm****5(b)**

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Posted: **Mon Feb 05, 2018 10:39 pm**

Posted: **Tue Feb 13, 2018 8:37 am**

Where is the problem 7?

Posted: **Thu Feb 15, 2018 9:39 am**

Here you can get the full solution of No,7

Posted: **Sun Mar 04, 2018 8:25 am**

Posted: **Mon Feb 18, 2019 1:35 pm**

Posted: **Mon Feb 18, 2019 2:45 pm**

This link is corrupted.Here you can get the solution of problem no 3.

Posted: **Mon Feb 18, 2019 2:49 pm**

Problem no $6(b)$.

Posted: **Mon Feb 18, 2019 5:14 pm**

Problem 1(a)

Hard solution

$(n-1)×n×(n+1)=(n^2-n)(n+1)$[According to fermat's little theorem given expression is divided by $2$ ]

$(n-1)×n×(n+1)=(n^2-n)(n+1)=n^3-n$[According to fermat's little theorem given expression is divided by $3$ ]

So,$(n-1)×n×(n+1)$ is divided by $2×3$ or $6$.**Proved.**

Hard solution

$(n-1)×n×(n+1)=(n^2-n)(n+1)$[According to fermat's little theorem given expression is divided by $2$ ]

$(n-1)×n×(n+1)=(n^2-n)(n+1)=n^3-n$[According to fermat's little theorem given expression is divided by $3$ ]

So,$(n-1)×n×(n+1)$ is divided by $2×3$ or $6$.