How do you simplify sqrt (15x) * (21x)15x(21x)?

1 Answer
May 18, 2015

By exponentiial rules, we know that a^n*a^m=a^(n+m)anam=an+m

So, in this case, if we rewrite your product:

(15x)^(1/2)*(21x)=15^(1/2)*x^(1/2)*21x(15x)12(21x)=1512x1221x

We can sum the exponentials of the variable xx.

15^(1/2)*21x^(3/2)151221x32

Simpifying more, we can even factor the constants, as both are multplied by three:

5^(1/2)*color(green)(3(1/2))*7*color(green)(3)*x^(3/2)5123(12)73x32

5^(1/2)*7*3^(3/2)*x^(3/2)5127332x32

Transforming all these exponentials into roots:

7sqrt(5)sqrt((3x)^3)75(3x)3