Question

What is the value of the expression 8p4

Answer 1

`8P_4 = 1680`

Step-by-step explanation

We use the formula

`nP_r = (n!)/((n - r)!)`

For

`8P_4`

and n=8, r=4.

`8P_4= (8!)/((8- 4)!)`

This simplifies to

`8P_4= (8!)/(4!)`

We expand the numerator using factorial notation,

`8P_4= (8 * 7 * 6 * 5 * 4!)/(4!)`

The common factors cancel out.

`8P_4= 8 * 7 * 6 * 5`

`8P_4= 1680`