Permutation and CombinationHard
Question
2nPn is equal to
Options
A.(n + 1) ( n + 2) ..... (2n)
B.2n [1 . 3 . 5 .....(2n - 1)]
C.(2) . (6) . (10) .... (4n - 2)
D.n!(2nCn)
Solution
Value of 2npn is 
(i) (n + 1) (n + 2) ----- (2n) and n ! . 2nCn



= 2n (1.3.5.7. .....(2n - 1)) = (2. 6. 10. 14 ..... (4n - 2))
(i) (n + 1) (n + 2) ----- (2n) and n ! . 2nCn
= 2n (1.3.5.7. .....(2n - 1)) = (2. 6. 10. 14 ..... (4n - 2))
Create a free account to view solution
View Solution FreeMore Permutation and Combination Questions
A person has three different bags and four different books. The number of ways, in which he can put these books in the b...In how many ways can a selection of 4 letters be made out of the letters of the word ′MATHEMATICS′ ?...The number of ways in which 8 answer books be arranged so that the best and the worst do not occur together is-...Four dice are rolled. The number of possible outcomes in which at least one die shows 2 is-...The number of ways in which 3 different red, 3 different white and 3 different black balls can be arranged in a line suc...