Question

prove whether it is rational or irrational
$\frac{2 \sqrt{7} }{7 \sqrt{7} }$
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Answer 1

Explanation:

$Let us assume 21 is rational.</p><p></p><p>So we can write this number as</p><p></p><p>21=ba ---- (1)</p><p></p><p>Here, a and b are two co-prime numbers and b is not equal to zero.</p><p></p><p>Simplify the equation (1) multiply by 2 both sides, we get</p><p></p><p>1=ba2</p><p></p><p>Now, divide by b, we get</p><p></p><p>b=a2 or ab=2</p><p></p><p>Here, a and b are integers so, ab is a rational number, </p><p></p><p></p><p>so 2 should be a rational number.</p><p></p><p>But 2 is a irrational number, so it is contradictory.</p><p></p><p>Therefore, 21 is irrational number.</p><p></p><p>$

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Answer 2

Answer:

happy Diwali to u alll

Explanation:

enjoy your day

keep smiling