Упростить: (5а^2+6ab) +(a^2-ab) (3xy-y^3) -(2x^3-xy) 12x(x^3-x-1) +8x^3(6x-1) 13(a^3b-4a^2b+1)-5b(a^3-4a^2+2)-4a^2(2ab-8)

Упростим выражения:

1) (5а^2 + 6аb) + (a^2 - ab) = 5a^2 + 6ab + a^2 - ab = 6a^2 + 5ab;

2) (3xy - y^3) - (2x^3 - xy) = 3xy - y^3 - 2x^3 + xy = -y^3 - 2x^3 + 4xy;

3) 12x * (x^3 - x - 1) + 8x^3 * (6x - 1) = 12x^4 - 12x^2 - 12x + 48x^4 - 8x^3 = 60x^4 - 8x^3 - 12x^2 - 12x;

4) 13 * (a^3b - 4a^2b + 1) - 5b * (a^3 - 4a^2 + 2) - 4a^2 * (2ab - 8) = 13a^3b - 52a^2b + 13 - 5a^3b + 20a^2b - 10b - 8a^3b + 32a^2 = -32a^2b + 32a^2 - 10b + 13;

13a^3b - 5a^3b - 8a^3b = 13a^3b - 13a^3b = 0;

-52a^2b + 20a^2b = -32a^2b.