6. Упростите выражение 128x^2y^3 ⋅ (−1/4 xy^5)^3.

128x^2y^3 ⋅ (−1/4 xy^5)^3 = 128x^2y^3 ⋅ (−1/4)^3 ⋅ x^3 ⋅ y^(5*3) = 128x^2y^3 ⋅ −1/64 ⋅ x^3 ⋅ y^15 = −128/64 ⋅ x^(2+3) ⋅ y^(3+15) = −2x^5y^18.