Respuesta :

LammettHash

3 * 7 = 21, so

[tex]\sqrt{21}=\sqrt{3\cdot7}=\sqrt3\sqrt7[/tex]

Then

[tex]\dfrac{\sqrt3}{\sqrt{21}}=\dfrac1{\sqrt7}[/tex]

and you can rationalize the denominator to write this as

[tex]\dfrac1{\sqrt7}\cdot\dfrac{\sqrt7}{\sqrt7}=\dfrac{\sqrt7}7[/tex]

angie823

answer: √3⋅√21 = 3√7