Permutations And Combinations Question 89
Question: If $ ^{n^{2}-n}C_2{{=}^{n^{2}-n}}C _{10} $ , then $ n= $
Options:
A) 12
B) 4 only
C) $ -3 $ only
D) 4 or  $ -3 $
 Correct Answer: D $ \Rightarrow n^{2}-n-2=10 $  or  $ n=4,\ -3 $ .Show Answer
  Answer:
Solution:
 BETA
  BETA 
             
             
           
           
           
          