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If a = ⎡ ⎢ ⎣ 1 0 1 0 0 1 a B 2 ⎤ ⎥ ⎦ , Then Ai + Ba + 2 a 2 Equals - Mathematics

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प्रश्न

If \[A = \begin{bmatrix}1 & 0 & 1 \\ 0 & 0 & 1 \\ a & b & 2\end{bmatrix},\text{ then aI + bA + 2 }A^2\] equals ____________ .

विकल्प

  • A

  • -A

  • ab A

  • none of these

MCQ
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उत्तर

None of these

\[A = \begin{bmatrix}1 & 0 & 1 \\ 0 & 0 & 1 \\ a & b & 2\end{bmatrix}\]

\[ \Rightarrow A^2 = \begin{bmatrix}1 + a & b & 3 \\ a & b & 2 \\ 3a & 2b & a + b + 4\end{bmatrix}\]

Now,

\[aI + bA + 2 A^2 = \begin{bmatrix}a & 0 & 0 \\ 0 & a & 0 \\ 0 & 0 & a\end{bmatrix} + \begin{bmatrix}b & 0 & b \\ 0 & 0 & b \\ ab & b^2 & 2b\end{bmatrix} + \begin{bmatrix}2 + 2a & 2b & 6 \\ 2a & 2b & 4 \\ 6a & 6b & 2a + 2b + 8\end{bmatrix}\]

\[ = \begin{bmatrix}3a + b + 2 & 2b & b + 6 \\ 2a & a + 2b & b + 4 \\ ab + 6a & b^2 + 6b & 3a + 4b + 8\end{bmatrix}\]

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अध्याय 7: Adjoint and Inverse of a Matrix - Exercise 7.4 [पृष्ठ ३८]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 7 Adjoint and Inverse of a Matrix
Exercise 7.4 | Q 26 | पृष्ठ ३८

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