Answer:
C(n,n)=1
Step-by-step explanation:
C(n,n) means we have to find the combination when n objects are to be selected from n objects.
Formula for C(n,r) is
[tex]\dfrac{factorial\ n}{factorial\ r\times factorial\ (n-r)}[/tex]
Here, r=n
C(n,n) is equal to
[tex]\dfrac{factorial\ n}{factorial\ n\times factorial\ (n-n)}[/tex]
[tex]\dfrac{factorial\ n}{factorial\ n\times factorial\ (0)}[/tex]
since, factorial 0=1
Hence, C(n,n)=1