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Let a = ⎡ ⎢ ⎣ a 0 0 0 a 0 0 0 a ⎤ ⎥ ⎦ , Then an is Equal to - Mathematics

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प्रश्न

Let A = \[\begin{bmatrix}a & 0 & 0 \\ 0 & a & 0 \\ 0 & 0 & a\end{bmatrix}\], then An is equal to

 

विकल्प

  • \begin{bmatrix}a^n & 0 & 0 \\ 0 & a^n & 0 \\ 0 & 0 & a\end{bmatrix} 

  • \[\begin{bmatrix}a^n & 0 & 0 \\ 0 & a & 0 \\ 0 & 0 & a\end{bmatrix}\]

  • \[\begin{bmatrix}a^n & 0 & 0 \\ 0 & a^n & 0 \\ 0 & 0 & a^n\end{bmatrix}\]

  •  \[\begin{bmatrix}na & 0 & 0 \\ 0 & na & 0 \\ 0 & 0 & na\end{bmatrix}\]

MCQ

उत्तर

 \[\begin{bmatrix}a^n & 0 & 0 \\ 0 & a^n & 0 \\ 0 & 0 & a^n\end{bmatrix}\]

\[Here, \]

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

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

\[ \Rightarrow A^3 = \begin{bmatrix}a^2 & 0 & 0 \\ 0 & a^2 & 0 \\ 0 & 0 & a^2\end{bmatrix}\begin{bmatrix}a & 0 & 0 \\ 0 & a & 0 \\ 0 & 0 & a\end{bmatrix} = \begin{bmatrix}a^3 & 0 & 0 \\ 0 & a^3 & 0 \\ 0 & 0 & a^3\end{bmatrix}\]

\[\]

This pattern is applicable on all natural numbers .

\[ \therefore A^n = \begin{bmatrix}a^n & 0 & 0 \\ 0 & a^n & 0 \\ 0 & 0 & a^n\end{bmatrix}\]

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अध्याय 5: Algebra of Matrices - Exercise 5.7 [पृष्ठ ६६]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 5 Algebra of Matrices
Exercise 5.7 | Q 8 | पृष्ठ ६६

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