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the value of the determinant |{:(.^(...

the value of the determinant
`|{:(.^(n)C_(r-1),,.^(n)C_(r),,(r+1)^(n+2)C_(r+1)),(.^(n)C_(r),,.^(n)C_(r+1),,(r+2)^(n+2)C_(r+2)),(.^(n)C_(r+1),,.^(n)C_(r+2),,(r+3)^(n+2)C_(r+3)):}|` is

A

`n^(2)+n-1)`

B

`0`

C

`.^(n+3)C_(r+3)`

D

`.^(n)C_(r-1)+^(n)C_(r)+^(n)C_(r+1)`

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To find the value of the determinant \[ D = \begin{vmatrix} {n \choose r-1} & {n \choose r} & (r+1) {n+2 \choose r+1} \\ {n \choose r} & {n \choose r+1} & (r+2) {n+2 \choose r+2} \\ {n \choose r+1} & {n \choose r+2} & (r+3) {n+2 \choose r+3} \end{vmatrix} \] we will follow these steps: ### Step 1: Simplify the third column The elements of the third column can be expressed in terms of binomial coefficients. We can factor out the common terms in the third column. - The first element is \((r+1) {n+2 \choose r+1}\) - The second element is \((r+2) {n+2 \choose r+2}\) - The third element is \((r+3) {n+2 \choose r+3}\) Factoring out \({n+2}\) from the third column gives us: \[ D = {n+2} \begin{vmatrix} {n \choose r-1} & {n \choose r} & {n+1 \choose r+1} \\ {n \choose r} & {n \choose r+1} & {n+1 \choose r+2} \\ {n \choose r+1} & {n \choose r+2} & {n+1 \choose r+3} \end{vmatrix} \] ### Step 2: Apply the identity for binomial coefficients Using the identity \( {n \choose r} + {n \choose r+1} = {n+1 \choose r+1} \), we can manipulate the determinant. We will add the first column to the second column: \[ D = {n+2} \begin{vmatrix} {n \choose r-1} & {n+1 \choose r} & {n+1 \choose r+1} \\ {n \choose r} & {n+1 \choose r+1} & {n+1 \choose r+2} \\ {n \choose r+1} & {n+1 \choose r+2} & {n+1 \choose r+3} \end{vmatrix} \] ### Step 3: Identify identical columns Notice that the first and third columns are identical: \[ \begin{vmatrix} {n \choose r-1} & {n+1 \choose r} & {n+1 \choose r} \\ {n \choose r} & {n+1 \choose r+1} & {n+1 \choose r+1} \\ {n \choose r+1} & {n+1 \choose r+2} & {n+1 \choose r+2} \end{vmatrix} \] ### Step 4: Conclude the determinant value Since two columns of the determinant are identical, the value of the determinant is zero: \[ D = 0 \] ### Final Answer Thus, the value of the determinant is: \[ \boxed{0} \]

To find the value of the determinant \[ D = \begin{vmatrix} {n \choose r-1} & {n \choose r} & (r+1) {n+2 \choose r+1} \\ {n \choose r} & {n \choose r+1} & (r+2) {n+2 \choose r+2} \\ {n \choose r+1} & {n \choose r+2} & (r+3) {n+2 \choose r+3} \end{vmatrix} ...
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.^(n)C_(r)+2.^(n)C_(r-1)+.^(n)C_(r-2)=

the roots of the equations |{:(.^(x)C_(r),,.^(n-1)C_(r),,.^(n)C_(r)),(.^(x+1)C_(r),,.^(n)C_(r),,.^(n+1)C_(r)),(.^(x+2)C_(r),,.^(n+1)C_(r),,.^(n+2)C_(r)):}|=0

""^(n)C_(r+1)+^(n)C_(r-1)+2.""^(n)C_(r)=

The value of determinant |[ ^n C_(r-1), ^n C_r, (r+1)^(n+2)C_(r+1)],[ ^n C_r, ^n C_(r+1),(r+2)^(n+2)C_(r+2)],[ ^n C_(r+1), ^n C_(r+2), (r+3)^(n+2)C_(r+3)]| is n^2+n-2 b. 0 c. ^n+3C_(r+3) d. ^n C_(r-1)+^n C_r+^n C_(r+1)

""^(n) C_(r+1)+2""^(n)C_(r) +""^(n)C_(r-1)=

Prove that .^(n)C_(r )+.^(n-1)C_(r )+..+.^(r )C_(r )=.^(n+1)C_(r+1)

""^(n)C_(n-r)+3.""^(n)C_(n-r+1)+3.""^(n)C_(n-r+2)+""^(n)C_(n-r+3)=""^(x)C_(r)

For ""^(n) C_(r) + 2 ""^(n) C_(r-1) + ""^(n) C_(r-2) =

f(n)=sum_(r=1)^(n) [r^(2)(""^(n)C_(r)-""^(n)C_(r-1))+(2r+1)(""^(n)C_(r ))] , then

""^(n)C_(r)+2""^(n)C_(r-1)+^(n)C_(r-2) is equal to

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