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If S = [ a B C D ] , Then Adj a is (A) [ − D − B − C a ] (B) [ D − B − C a ] (C) [ D B C a ] (D) [ D C B a ] - Mathematics

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प्रश्न

If \[S = \begin{bmatrix}a & b \\ c & d\end{bmatrix}\], then adj A is ____________ .

विकल्प

  • \[\begin{bmatrix}- d & - b \\ - c & a\end{bmatrix}\]

  • \[\begin{bmatrix}d & - b \\ - c & a\end{bmatrix}\]

  • \[\begin{bmatrix}d & b \\ c & a\end{bmatrix}\]

  • \[\begin{bmatrix}d & c \\ b & a\end{bmatrix}\]

MCQ
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उत्तर

\[\begin{bmatrix}d & - b \\ - c & a\end{bmatrix}\]

Adjoint of a square matrix of order 2 is obtained by interchanging the diagonal elements and changing the signs of off-diagonal elements.

Here,

\[A = \begin{bmatrix} a & b\\c & d \end{bmatrix}\]

\[ \Rightarrow adj A = \begin{bmatrix} d & - b\\ - c & a \end{bmatrix}\]

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अध्याय 7: Adjoint and Inverse of a Matrix - Exercise 7.4 [पृष्ठ ३७]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 7 Adjoint and Inverse of a Matrix
Exercise 7.4 | Q 4 | पृष्ठ ३७

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