MCQ
Which of the following is not a rational number ?
- A$\sqrt{25}$
- B$\sqrt{9}$
- ✓$\sqrt{8}$
- D$\sqrt{16}$
✓
Answer
Correct option: C.
$\sqrt{8}$
$\sqrt{16}=\sqrt{4}\times\sqrt{4}=4 $ is a rational number
$\sqrt{9}=\sqrt{3} \times \sqrt{3}=3 $ is rational number
$\sqrt{25}=\sqrt{5}\times\sqrt{5}=5 $ is also a rational number
but $ \sqrt{8}$ is not a rational number
because $\sqrt{8}=2\sqrt{2}$ and $\sqrt{2} $ is an irrational
therefore. $\sqrt{8}$ is also an irrational number.
$\sqrt{9}=\sqrt{3} \times \sqrt{3}=3 $ is rational number
$\sqrt{25}=\sqrt{5}\times\sqrt{5}=5 $ is also a rational number
but $ \sqrt{8}$ is not a rational number
because $\sqrt{8}=2\sqrt{2}$ and $\sqrt{2} $ is an irrational
therefore. $\sqrt{8}$ is also an irrational number.
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