How do you multiply $(3sqrt5)(2sqrt 10)$ ?

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Answer 1 · 2015-05-03T19:36:02

This is easier if we first rearrange the sequence of the terms:
$(3sqrt(5))(2sqrt(10))$

$= (3*2)(sqrt(5)*sqrt(10))$

Noting that $sqrt(a)*sqrt(b) = sqrt(a*b)$
and that $sqrt(10) = sqrt(5)(sqrt(2)$

We can write
$= (6)(5sqrt(2))$

$=30sqrt(2)$

How do you multiply (3sqrt5)(2sqrt 10)(3sqrt5)(2sqrt 10)?