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The Binary Operation * is Defined By A * B = A2 + B2 + Ab + 1, Then (2 * 3) * 2 is Equal to - Mathematics

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Question

The binary operation * is defined by a * b = a2 + b2 + ab + 1, then (2 * 3) * 2 is equal to ______________ .

Options

  • 20

  • 40

  • 400

  • 445

MCQ
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Solution

445
Given: a * b = a2 + b2 + ab + 1

\[2 * 3 = 2^2 + 3^2 + 2 \times 3 + 1\]
        \[ = 4 + 9 + 6 + 1\]
        \[ = 20\]
\[\left( 2 * 3 \right) * 2 = 20 * 2\]
       \[ = {20}^2 + 2^2 + 20 \times 2 + 1\]
       \[ = 400 + 4 + 40 + 1\]
       \[ = 445\]

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Chapter 3: Binary Operations - Exercise 3.7 [Page 38]

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RD Sharma Mathematics [English] Class 12
Chapter 3 Binary Operations
Exercise 3.7 | Q 14 | Page 38

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