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Question
The value of `(2/5)^-2` is ______.
Options
`4/5`
`4/25`
`25/4`
`5/2`
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Solution
The value of `(2/5)^-2` is `underlinebb(25/4)`.
Explanation:
Using law of exponents,
`a^-m = 1/a^m` ...[∵ a is non-zero integer]
∴ `(2/5)^-2 = 1/(2/5)^2`
= `1/(4/25)`
= `25/4`
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