How do you simplify $sqrt(35) xx sqrt(15)$ ?

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Answer 1 · 2018-04-05T19:15:59

$5sqrt(21)$

You can 'split' roots

$sqrt(5xx7)xxsqrt(3xx5)$

$sqrt5xxsqrt7xxsqrt3xxsqrt5$

$sqrt5xxsqrt5xxsqrt(3xx7)$

$5sqrt(21)$
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Lets test this approach with numbers we know

$sqrt(16)=4" "$ Technically it is $+-4$ but lets ignore that.

$sqrt(4xx4) = sqrt(4)xxsqrt(4) = 2xx2 =4$

How do you simplify sqrt(35) xx sqrt(15)sqrt(35) xx sqrt(15)?