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If x is a positive integer, then |(x!,(x...

If x is a positive integer, then `|(x!,(x +1)!,(x +2)!),((x +1)!,(x +2)!,(x +3)!),((x +2)!,(x +3)!,(x +4)!)|` is equal to

A

`2x! (x +1) !`

B

`2x! (x +1) ! (x +2)!`

C

`2x ! (x +3)!`

D

`2(x +1) ! (x +2) ! (x _3)!`

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To solve the determinant \[ D = \begin{vmatrix} x! & (x+1)! & (x+2)! \\ (x+1)! & (x+2)! & (x+3)! \\ (x+2)! & (x+3)! & (x+4)! \end{vmatrix} \] we can simplify the factorials in the determinant. ### Step 1: Factor out common terms from each row 1. **First Row**: Factor out \(x!\): \[ x! \begin{vmatrix} 1 & x+1 & (x+2) \\ (x+1)! & (x+2)! & (x+3)! \\ (x+2)! & (x+3)! & (x+4)! \end{vmatrix} \] 2. **Second Row**: Factor out \((x+1)!\): \[ (x+1)! \begin{vmatrix} 1 & 1 & (x+2) \\ 1 & (x+2) & (x+3) \\ (x+2)! & (x+3)! & (x+4)! \end{vmatrix} \] 3. **Third Row**: Factor out \((x+2)!\): \[ (x+2)! \begin{vmatrix} 1 & 1 & 1 \\ 1 & 1 & (x+3) \\ 1 & (x+3) & (x+4) \end{vmatrix} \] Now, we have: \[ D = x! (x+1)! (x+2)! \begin{vmatrix} 1 & 1 & 1 \\ 1 & 1 & (x+3) \\ 1 & (x+3) & (x+4) \end{vmatrix} \] ### Step 2: Evaluate the 3x3 determinant Now we will evaluate the determinant: \[ \begin{vmatrix} 1 & 1 & 1 \\ 1 & 1 & (x+3) \\ 1 & (x+3) & (x+4) \end{vmatrix} \] Using the determinant formula, we can expand this determinant: \[ = 1 \cdot \begin{vmatrix} 1 & (x+3) \\ (x+3) & (x+4) \end{vmatrix} - 1 \cdot \begin{vmatrix} 1 & (x+3) \\ 1 & (x+4) \end{vmatrix} + 1 \cdot \begin{vmatrix} 1 & 1 \\ 1 & (x+3) \end{vmatrix} \] Calculating each of these 2x2 determinants: 1. \(\begin{vmatrix} 1 & (x+3) \\ (x+3) & (x+4) \end{vmatrix} = 1 \cdot (x+4) - (x+3) \cdot (x+3) = x + 4 - (x^2 + 6x + 9) = -x^2 - 5x - 5\) 2. \(\begin{vmatrix} 1 & (x+3) \\ 1 & (x+4) \end{vmatrix} = 1 \cdot (x+4) - (x+3) \cdot 1 = x + 4 - (x + 3) = 1\) 3. \(\begin{vmatrix} 1 & 1 \\ 1 & (x+3) \end{vmatrix} = 1 \cdot (x+3) - 1 \cdot 1 = x + 3 - 1 = x + 2\) Putting it all together: \[ = -x^2 - 5x - 5 - 1 + (x + 2) = -x^2 - 4x - 4 \] ### Step 3: Final Calculation Now substituting back into our expression for \(D\): \[ D = x! (x+1)! (x+2)! (-x^2 - 4x - 4) \] ### Conclusion Thus, the final result is: \[ D = -x! (x+1)! (x+2)! (x^2 + 4x + 4) \]

To solve the determinant \[ D = \begin{vmatrix} x! & (x+1)! & (x+2)! \\ (x+1)! & (x+2)! & (x+3)! \\ (x+2)! & (x+3)! & (x+4)! \end{vmatrix} ...
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OBJECTIVE RD SHARMA ENGLISH-DETERMINANTS-Section I - Solved Mcqs
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  9. if the system of linear equations {:(x+2ay+az=0),(x+3by+bz=0),(x+4c...

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  10. If alpha is a non-real cube root of -2, then the value of |(1,2 alpha,...

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  13. If omega is a non-real cube root of unity, then Delta = |(a(1) + b(1) ...

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  14. If Delta(r) = |(1,r,2^(r)),(2,n,n^(2)),(n,(n(n+1))/(2),2^(n+1))|, then...

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  15. If Delta(r) = |(2^(r -1),((r +1)!)/((1 + 1//r)),2r),(a,b,c),(2^(n) -1,...

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  16. The value of the determinant Delta = |(1 + a(1) b(1),1 + a(1) b(2),1 +...

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  17. If a,b,c are comples number and z=|{:(,0,-b,-c),(,bar(b),0,-a),(,bar(c...

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  18. The value of the determinant Delta = |(sin 2 alpha,sin (alpha + beta),...

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  19. If A, B and C denote the angles of a triangle, then Delta = |(-1,cos...

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  20. If X,Y and Z are opositive number such that Y and Z have respectively ...

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