How do you find the value of the permutation P(4,2)?

1 Answer
May 25, 2018

Answer:

#12#

Explanation:

#"using the definition"#

#•color(white)(x)^nP_r=(n!)/((n-r)!)#

#"where "n! =n(n-1)(n-2)xx... xx3xx2xx1#

#color(white)(x)^4P_2=(4!)/((4-2)!)=(4!)/(2!)#

#color(white)(xxxxxxxxxx)=(4xx3xxcancel(color(red)(2xx1)))/cancel(color(red)(2xx1))=4xx3=12#