If `^n-1C_r=(k^2-3)^n C_(r+1),t h e nk in ` `(-oo,-2]` b. `[2,oo)` c. `[-sqrt(3),sqrt(3)]` d. `(sqrt(3),2]`

Options

A. `[-sqrt3,sqrt3]`
B. `(-oo,-2)`
C. `(2,-oo)`
D. `(sqrt3,2]`

Explanation

We have,
`k^(2)-3=(""^(n-1)C_(r))/(""^(n)C _(r+1))`, where `0lerlen-1`
`impliesk^(2)-3=((n-1)!)/(r!(n-r-1)!)xx((n-r-1)!(r+1)!)/(n!)`
`impliesk^(2)-3=(r+1)/(n)`
`implies(1)/(n)lek^(2)-3le1" "[:'0lerlen-1implies1ler+1len]`
`implies2ltk^(2)lt4implieskin(sqrt3,2]`