मराठी

If a = ⎡ ⎢ ⎣ 1 0 0 0 1 0 a B − 1 ⎤ ⎥ ⎦ , Then A2 is Equal to ___________ . - Mathematics

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प्रश्न

If \[A = \begin{bmatrix}1 & 0 & 0 \\ 0 & 1 & 0 \\ a & b & - 1\end{bmatrix}\] , then A2 is equal to ___________ .

पर्याय

  • a null matrix

  • a unit matrix

  • A

MCQ

उत्तर

a unit matrix

\[A^2 = AA\] 

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

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

\[ \Rightarrow A^2 = \begin{bmatrix}1 & 0 & 0 \\ 0 & 1 & 0 \\ 0 & 0 & 1\end{bmatrix}\]

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पाठ 5: Algebra of Matrices - Exercise 5.7 [पृष्ठ ६५]

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आरडी शर्मा Mathematics [English] Class 12
पाठ 5 Algebra of Matrices
Exercise 5.7 | Q 1 | पृष्ठ ६५

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