Question 88643
{{{sqrt(81*x^4)}}}

{{{sqrt(81*x^2*x^2)}}} Factor {{{x^4}}} into {{{x^2*x^2}}}
 
{{{sqrt(81)*sqrt(x^2)*sqrt(x^2)}}} Break up the square roots using the identity {{{sqrt(x*y)=sqrt(x)*sqrt(y)}}}
 
{{{9*sqrt(x^2)*sqrt(x^2)}}} Take the square root of the perfect square 81 to get 9
 
{{{9*x*x}}} Take the square root of the perfect squares {{{x^2}}} to get {{{x}}} 
 
{{{9*x^2}}} Multiply the common terms 


So {{{sqrt(81*x^4)}}} simplifies to {{{9*x^2}}}