COMEDK · Maths · 28. Indefinite Integration
The sum of three numbers is 20 .
If we multiply the first number by 2 and add the second number to the result, and subtract the third number, we get 23 .
By adding second and third numbers to three times the first number, we get 46.
The above situation can be represented in matrix form as \(A X=B\) then the value of determinant formed by the cofactors of matrix A is
- A 16
- B -4
- C 36
- D -64
Answer & Solution
Correct Answer
(A) 16
Step-by-step Solution
Detailed explanation
Let the three numbers be \(x, y, z\). The given conditions are: \(x + y + z = 20\) \(2x + y - z = 23\) \(3x + y + z = 46\) The matrix \(A\) is given by: \(A = \begin{pmatrix} 1 & 1 & 1 \\ 2 & 1 & -1 \\ 3 & 1 & 1 \end{pmatrix}\) The determinant of \(A\) is…
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