1.

Find the number of positive integers `n` such that 105 is a divisor of `n^(2)+n+1`

Answer» The digit in the unit place of `n(n+1)+1` is 1,3, or 7
`implies` 5 does not divides `n^(2)+n+1`
`implies` 105 is not a divisor of `n(n+1)+1`,


Discussion

No Comment Found

Related InterviewSolutions