Question

Proge that: P (n, n) = P (n, n-1) ​

Answer 1

This is a simple proving. I hope that you know Permutation Formula. So, Let's Solve!

Solution: P = n!/(n - r)! [Formula to Remember]

L.H.S → P (n, n) = n!/(n - n)! = n!/0!

We know that value of 0! is 1.

→ P (n, n) = n!

R.H.S → P (n, n - 1) = n!/[n - (n - 1)]!

→ n!/( n - n + 1)! → n!/1! = n!

Since, L.H.S = R.H.S hence we can say that this proved. Happy Learning :)

Answer 2

p = n!/( n - r )!

L.H.S = P ( n, n ) = n!/(n - n)! = n!/0/

we know value of 0 is 1

P =(n,n) = n

R.H.S = P (n,n-1) = n [n-(n -1)]