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If (2 le r le n). then ""^(n)C(r) + 2. "...

If `(2 le r le n)`. then `""^(n)C_(r) + 2. ""^(n)C_(r+2)` is equal to

A

`2 ""^(n)C_(r+2)`

B

`""^(n+1)C_(r+1)`

C

`""^(n+2)C_(r+2)`

D

`""^(n+1)C_(r)`

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Knowledge Check

  • If (2lerlen) , then ""^(n)C_(r)+2.""^(n)C_(r+1)+""^(n)C_(r+2) is equal to

    A
    `2.""^(n)C_(r+2)`
    B
    `""^(n+1)C_(r+1)`
    C
    `""^(n+2)C_(r+2)`
    D
    `""^(n+1)C_(r)`

  • If .^(n)P_(r)=x.^(n)C_(r) x=

    A
    `.^(n)P_(r-1)`
    B
    `.^(n)C_(r-1)`
    C
    `n!`
    D
    `r!`

  • .^(n-1)C_(r)+^(n-1)C_(r-1)=

    A
    `.^(n)C_(r+1)`
    B
    `.^(n)C_(r+1)`
    C
    `.^(n+1)C_(r)`
    D
    `.^(n)C_(r)`

    • Similar Questions

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