Evaluate
\frac{3\sqrt{7}}{4}+\frac{21}{20}\approx 3.034313483
Factor
\frac{3 \sqrt{7} {(\sqrt{7} + 5)}}{20} = 3.034313483298443
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\frac{21}{20}+\frac{5\times 3\sqrt{7}}{20}
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of 20 and 4 is 20. Multiply \frac{3\sqrt{7}}{4} times \frac{5}{5}.
\frac{21+5\times 3\sqrt{7}}{20}
Since \frac{21}{20} and \frac{5\times 3\sqrt{7}}{20} have the same denominator, add them by adding their numerators.
\frac{21+15\sqrt{7}}{20}
Do the multiplications in 21+5\times 3\sqrt{7}.
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Limits
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