a) (3a³x²₋15a⁴x⁶)÷(5ax) = 3/5a-¹x^-4 - 3a³x^5
b) 6x³₋60x⁴₋3x³₋9x⁴)÷(3x³)= 2 -20x - 1 - 3x
c) (4ab₋2a³b²₊20a²b⁵)·(2a²b³) = 8a³b^4 - 4a^5 b^5 + 40a^4 b^8
d) (40a³x₋12a⁴x²₊16a⁵x⁴)÷(2a²x²) = 20ax-¹ - 6a² + 8a³x²
e) 6ac⁴₋8a²c³₊4a³c⁵)·(3ac³) = 18a²c^7 - 24a³c^6 + 12a^4c^8
