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Maharashtra State BoardHSC Science (General) 12th Standard Board Exam

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Transform [1243-15246] into an upper triangular matrix by using suitable row transformations - Mathematics and Statistics

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Question

Transform $[\begin{matrix} 1 & 2 & 4 \\ 3 & - 1 & 5 \\ 2 & 4 & 6 \end{matrix}]$ into an upper triangular matrix by using suitable row transformations

Sum

Solution

Let A = $[\begin{matrix} 1 & 2 & 4 \\ 3 & - 1 & 5 \\ 2 & 4 & 6 \end{matrix}]$

Applying R₂ → R₂ – 3R₁ and R₃ → R₃ – 2R₁, we get

$[\begin{matrix} 1 & 2 & 4 \\ 0 & - 7 & - 7 \\ 0 & 0 & - 2 \end{matrix}]$

This is required upper triangular matrix.

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Chapter 1.2: Matrics - Short Answers I

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SCERT Maharashtra Mathematics and Statistics (Arts and Science) [English] 12 Standard HSC

Chapter 1.2 Matrics
Short Answers I | Q 11

SCERT Maharashtra Mathematics and Statistics (Arts and Science) [English] 12 Standard HSC

Chapter 1.2 Matrics
Short Answers II | Q 11

2020-2021 (April) Shaalaa.com Model Set 2 (with solutions)

Q 17 | 3 marks

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