(4x^2y^3z^5)^3
------------------- Your going to multiply everything by 3
(2x^5y^2z^6)^3
12x^6y^9z^15
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6x^15y^6z^18 Then you'll cancel things out. And remember you cant cancel exponents and variables that aren't the same.
So 12/6=2 x^15-x^6=x^9 y^9-y^6=y^3 z^18-z^15^3
If you cancel all the numbers to the top you get negative so I did it that you come out all positive.
2y^3
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x^9z^3
If you want it all at the top it'll be 2x^-9y^3z^-3