PROBLEM 15E

Prove Equation 1.2-2. Hint: First select n1 positions in ways, Then select n2 from the remaining n - n1 position in ways and so on. Finally, use the multiplication rule.

Answer :

Step 1 of 1 :

The claim is to prove =

We have, positions in ways and then select from the n - ways

We have to use the multiplication rule.

We have to arrange n objects

can place ways

And can place ways

Similarly,

Therefore,

= ……...

=

Hence the proof