Evaluate
\frac{\sqrt{21}}{14}\approx 0.327326835
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\frac{3\sqrt{21}}{2\left(\sqrt{21}\right)^{2}}
Rationalize the denominator of \frac{3}{2\sqrt{21}} by multiplying numerator and denominator by \sqrt{21}.
\frac{3\sqrt{21}}{2\times 21}
The square of \sqrt{21} is 21.
\frac{\sqrt{21}}{2\times 7}
Cancel out 3 in both numerator and denominator.
\frac{\sqrt{21}}{14}
Multiply 2 and 7 to get 14.
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