Question
Check whether $7 \sqrt{5}, \frac{7}{\sqrt{5}}, \sqrt{2}+21, \pi-2$, are irrational numbers or not.
✓
Answer
Recall that (I) $\sqrt{p}$ is always an irrational number where p is prime number.$(ii)$ Sum of a rational and irrational number is always irrational.
Thus
$7 \sqrt{5} , \frac{7}{\sqrt{5}}$ $\sqrt{2}$ $+ 21, \pi – 2$
So, all these are irrational numbers.
Thus
$7 \sqrt{5} , \frac{7}{\sqrt{5}}$ $\sqrt{2}$ $+ 21, \pi – 2$
So, all these are irrational numbers.
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