How do you simplify $\frac{\sqrt{21}}{\sqrt{15}}$ $sqrt21/sqrt15$ ?

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Answer 1 · 2016-09-09T19:37:08

$\sqrt{\frac{7}{5}} = \frac{\sqrt{35}}{5}$ $sqrt(7/5) = sqrt35/5$

It is debatable which one would be considered "simpler'

Two square roots being divided can be combined into one:

$\frac{\sqrt{21}}{\sqrt{15}} = \sqrt{\frac{21}{15}} \leftarrow$ $sqrt21/sqrt15 = sqrt(21/15)" "larr$ this can be simplified.

$sqrt(21/15) = sqrt((cancel3xx7)/(cancel3xx5))$

= $sqrt(7/5)$

It is possible then to rationalise the denominator

$sqrt(7/5) = sqrt7/sqrt5 xx sqrt5/sqrt5$

= $sqrt35/5$

How do you simplify sqrt21/sqrt15√21√15sqrt21/sqrt15?