Home
Class 11
MATHS
If (n!)/(2!(n-2)!):(n!)/(4!(n-4)!) =2:1....

If `(n!)/(2!(n-2)!):(n!)/(4!(n-4)!) =2:1`. Find the value of n.

Promotional Banner

Topper's Solved these Questions

  • PERMUTATIONS AND COMBINATIONS

    JBD PUBLICATION|Exercise EXAMPLE|59 Videos

  • MODEL PAPER (8)

    JBD PUBLICATION|Exercise EXERICSE|41 Videos

  • PRINCIPLE OF MATHEMATICAL INDUCTION

    JBD PUBLICATION|Exercise EXAMPLE|11 Videos

Similar Questions

Explore conceptually related problems

If .^(2n)C_(3):^(n)C_(3)=11:1 , find the value of n.

If ""^(2n+1)P_(n-1): ""^(2n-1)P_n =3:5 then the value of n equals :

Let f be a continuous function on R such that f (1/(4n))=sin e^n/(e^(n^2))+n^2/(n^2+1) Then the value of f(0) is

If .^(m+n)P_(2)=90 and .^(m-n)P_(2)=30 , find the value of m and n is equal to.

If sum_(n=0)^(oo)2cot^(-1)((n^(2)+n+4)/(2))=k pi , then find the value of k.

If (n+2)! =(2550)(n!), find n.

If n is a positive integer satisfying the equation 2+(6*2^(2)-4*2)+(6*3^(2)-4*3)+"......."+(6*n^(2)-4*n)=140 then the value of n is

The coefficient of 1//x in the expansion of (1+x)^n(1+1//x)^n is (a). (n !)/((n-1)!(n+1)!) (b). ((2n)!)/((n-1)!(n+1)!) (c). ((2n)!)/((2n-1)!(2n+1)!) (d). none of these

Let Delta_(a)=|{:((a-1),n,6),((a-1)^(2), 2n^(2),4n-2),((a-1)^(3),3n^(3),3n^(2)-3n):}| the value of sum_(a=1)^(n)Delta_(a) is

Find the sum of the series 1*n+2*(n-1)+3*(n-2)+4*(n-3)+"..."+(n-1)*2+n*1 also, find the coefficient of x^(n-1) in th cxpansion of (1+2x+3x^(2)+"...."nx^(n-1))^(2) .

JBD PUBLICATION-PERMUTATIONS AND COMBINATIONS-EXAMPLE
  1. How many 3-digit numbers can be formed from the digits 1, 2, 3, 4 and ...

    Text Solution

    |

  2. How many 3-digit numbers can be formed from the digits 1, 2, 3, 4 and ...

    Text Solution

    |

  3. If (n!)/(2!(n-2)!):(n!)/(4!(n-4)!) =2:1. Find the value of n.

    Text Solution

    |

  4. show that 2^16 divides 32!. also, find the largest value of n for whic...

    Text Solution

    |

  5. What is the largest power of 2 contained in 32!.

    Text Solution

    |

  6. How many different words (with or without meaning) can be formed using...

    Text Solution

    |

  7. Find the value of n such that ""^nP5 = 42 ""^nP3,,n gt 4.

    Text Solution

    |

  8. Find n if "^(n-1)P3 : "^nP4 =1:9.

    Text Solution

    |

  9. Find r if "^5Pr =2 "^6P(r-1).

    Text Solution

    |

  10. How many words, with or without meaning can be made from the letters o...

    Text Solution

    |

  11. How many words, with or without meaning can be made from the letters o...

    Text Solution

    |

  12. How many words, with or without meaning can be made from the letters o...

    Text Solution

    |

  13. How many words, with or without meaning can be made from the letters o...

    Text Solution

    |

  14. How many words can be formed by using the letters of the word 'ORIENTA...

    Text Solution

    |

  15. There are three prizes to be distributed among 6 students. In how many...

    Text Solution

    |

  16. There are three prizes to be distributed among 6 students. In how many...

    Text Solution

    |

  17. There are three prizes to be distributed among 6 students. In how many...

    Text Solution

    |

  18. In how many ways can the letters of the word ASSASSINATION be arranged...

    Text Solution

    |

  19. In how many ways can be letters of word 'ASSASSINATION' be arranged so...

    Text Solution

    |

  20. How many different words, with or without meaning can be formed by usi...

    Text Solution

    |