How do you simplify #sqrt21/sqrt15#?

Question

2013 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-09-09T19:37:08

#sqrt(7/5) = sqrt35/5#

It is debatable which one would be considered "simpler'

Two square roots being divided can be combined into one:

#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#