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The value of -25×-9 is ______. - Mathematics

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Question

The value of `sqrt(-25) xx sqrt(-9)` is ______.

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Solution

The value of `sqrt(-25) xx sqrt(-9)` is – 15.

Explanation:

 `sqrt(-25) xx sqrt(-9) = sqrt(-1) . sqrt(25) xx sqrt(-1) . sqrt(9)`

= 5i × 3i

= 15i2

= –15

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Chapter 5: Complex Numbers and Quadratic Equations - Exercise [Page 93]

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NCERT Exemplar Mathematics [English] Class 11
Chapter 5 Complex Numbers and Quadratic Equations
Exercise | Q 25.(ii) | Page 93

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