Question 202372
whenever  a  radical  is  in  denominator,  it  is  cleared  by  multiplying  num  and  dem  by that  radical. Remember sqrt(a) *sqrt(a) =(a)
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sqrt(3/5) = sqrt3/sqrt5= {sqrt3*sqrt5} / {sqrt5*sqrt5} = sqrt(15)/5
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3sqrt(13/3) ={3*sqrt(13)} / sqrt(3)= {3*sqrt13*sqrt3}/sqrt(3)*sqrt(3)={3*sqrt(39)}/3 =sqrt(39)