Question

Упростите
1) 15(8х-1)-8(15х+4)
2) 5b(3a-b)-3a(5b+a)
3) a($2a^{2}$-3n)-n($2n^{2}$+a)

Answer 1

$15(8x-1)-8(15x+4)=120x-15-120x-32=-47\\5b(3a-b)-3a(5b+a)=15ab-5b^2-15ab-3a^2=-3a^2-5b^2\\a(2a^2-3n)-n(2n^2+a)=2a^3-3an-2n^3-an=2a^3-4an-2n^3$