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Question
Which of the following is irrational?
Options
`sqrt(4/9)`
`sqrt(12)/sqrt(3)`
`sqrt(7)`
`sqrt(81)`
Solution
`bb(sqrt(7))`
Explanation:
Irrational numbers are real numbers which cannot be represented as simple fractions.
Examples: `sqrt(2), sqrt(3), pi`
`sqrt(4/9) = 2/3` ...(Rational)
`sqrt(12)/sqrt(3) = (2sqrt(3))/sqrt(3) = 2` ...(Rational)
`sqrt(81) = 9` ...(Rational)
But `sqrt(7)` is an irrational number.
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