Handshakes Formula

Algebra Level pending

At a party, each guest shook hands with each of the others. If there are n n people, which of the following is the expression for the number of handshakes of n n people?

Can you explain why?

2 n \large 2^n n ( n − 1 ) 2 \large \frac{n(n-1)}{2} n 2 \large n^2 n 2 2 \large \frac{n^2}{2}

Barry Leung by Barry Leung , 17, Hong Kong

This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try refreshing the page, (b) enabling javascript if it is disabled on your browser and, finally, (c) loading the non-javascript version of this page . We're sorry about the hassle.

1 solution

Lâm Lê
Aug 18, 2020

It’s also the n - 1th triangular number \text{It's also the n - 1th triangular number}

0 Helpful 0 Interesting 0 Brilliant 0 Confused

0 pending reports

×

Problem Loading...

Note Loading...

Set Loading...