4. Упростите выражение:
а) -2ab³ ⋅ 3a²b⁴ = -2 ⋅ 3 ⋅ a ⋅ a² ⋅ b³ ⋅ b⁴ = -6a^(1+2)b^(3+4) = -6a³b⁷
б) (-2a²b³)² = (-2)² ⋅ (a²)² ⋅ (b³)² = 4a^(2⋅2)b^(3⋅2) = 4a⁴b⁶
Ответ: а) -6a³b⁷; б) 4a⁴b⁶