Evaluate
\frac{\sqrt{21}}{4}\approx 1.145643924
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\frac{3\sqrt{7}\sqrt{3}}{4\left(\sqrt{3}\right)^{2}}
Rationalize the denominator of \frac{3\sqrt{7}}{4\sqrt{3}} by multiplying numerator and denominator by \sqrt{3}.
\frac{3\sqrt{7}\sqrt{3}}{4\times 3}
The square of \sqrt{3} is 3.
\frac{3\sqrt{21}}{4\times 3}
To multiply \sqrt{7} and \sqrt{3}, multiply the numbers under the square root.
\frac{3\sqrt{21}}{12}
Multiply 4 and 3 to get 12.
\frac{1}{4}\sqrt{21}
Divide 3\sqrt{21} by 12 to get \frac{1}{4}\sqrt{21}.
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