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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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