quick math question!?

√(64x^3y^6)
= √[8^2 * x^2 * (y^3)^2 * x]
= √(8^2) * √(x^2) * √(y^3)^2 * √x
= 8 * x * y^3 * √x
= 8xy^3√x

I would suggest that what you have typed is NOT WHAT YOU MEAN.

What you have typed MUST be read as :-

( √64 ) ( x^3 ) ( y^6 )

8 x^3 y^6

What you PROBABLY mean is :-

√ [ 64 x^3 y^6 ]

8 x^(3/2) y^3

8xy^3√x

sqrt((2^6)*(x^2)*x*y^6) = 8*x*(y^3)*sqrt(x)