Question

Помогиите плизз алгебра 7 класс

Answer 1

$\displaystyle (3-n^3)^3-n^2(7n^4-n^7-15n)=\\\\=(3^3-3*3^2*n^3+3*3*(n^3)^2-(n^3)^3)-7n^6+n^9+15n^3=\\\\=27-27n^3+9n^6-n^9-7n^6+n^9+15n^3=\\\\=2n^6-12n^3+27$

$\displaystyle a=2; b=-12, c=27$

при n= -1

$\displaystyle 2*(-1)^6-12*(-1)^3+27=2+12+27=41$