text: When you have (x^a)^b, that is the same as x^(a+b)\n\nSo you have:\n3^-3 x^(2-3) y^(-4-3)\n\nThis simplifies to:\n27^-1 x^-1 y^-7\n\nNow put all negative exponents in the denominator:\n.... 1\n----------\n27 x y^7