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A binary operation * on the set of rational numbers is defined as \(x \asty = \frac{x^2 ...

A binary operation * on the set of rational numbers is defined as \(x \ast y = \frac{x^2 - y^2}{2xy}\). Find \(-5 \ast 3\)
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  • A \(\frac{-8}{15}\)
  • B \(\frac{8}{15}\)
  • C \(\frac{17}{15}\)
  • D \(\frac{-17}{15}\)
Correct Answer: Option A
Explanation:
\(x \ast y = \frac{x^2 - y^2}{2xy}\\
=\frac{(x+y)(x-y)}{2xy}\\
-5 \ast 3 =\frac{(-5+3)(-5-3)}{2(-5\times3)}\\
=\frac{-2 \times -8}{2(-5\times3)}\\
=\frac{-8}{15}\)

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