Download the app

Questions  

The product of r consecutive positive integers is divisible by

Remember concepts with our Masterclasses.

80k Users
60 mins Expert Faculty Ask Questions
a
r!
b
(r – 1)!
c
(r + 1)!
d
None of these

Ready to Test Your Skills?

Check Your Performance Today with our Free Mock Tests used by Toppers!

detailed solution

Correct option is A

Let r consecutive positive integers bem, m + 1, m + 2, … (m + r – 1), where m ∈ N∴  Product =m(m+1)(m+2)…(m+r−1)=(m−1)!m(m+1)(m+2)…(m+r−1)(m−1)!=(m+r−1)!(m−1)!=r!⋅(m+r−1)!r!(m−1)!=r!⋅m+r−1Crwhich is divisible by r!          (∵ m + r – 1Cr is a natural number)


Similar Questions

 nCr+2nCr1+nCr2 is equal to


whats app icon
phone icon