Question

Разложите многочлен на множители и проверьте спрведливось умножением ПОМАГИТЕ 

Answer 1

$21xy^2-8y^2z-16z^3+42xz^2=(21xy^2+42xz^2)-(8y^2z+16z^3)= \ =21x(y^2+2z^2)-8z(y^2+2z^2)=(21x-8z)(y^2+2z^2)= \ =21x*y^2+21x*2z^2-8z*y^2-8z*2z^2= \ 21xy^2+42xz^2-8zy^2-16z^3$

$8abc^2+20a^2c-18b^3c-45ab^2=(8abc^2-18b^3c)+(20a^2c-45ab^2)= \ =2bc(4ac-9b^2)+5a(4ac-9b^2)=(2bc+5a)(4ac-9b^2)= \ =2bc*4ac+2bc*(-9b^2)+5a*4ac+5a*(-9b^2)= \ =8abc^2-18b^3c+20a^2c-45ab^2$

$-14mp+21p^2-15py+10my=(21p^2-14mp)+(10my-15py)= \ =7p(3p-2m)+5y(2m-3p)=7p(3p-2m)-5y(3p-2m)= \ =(7p-5y)(3p-2m)=7p*3p+7p*(-2m)-5y*3p-5y*(-2m)= \ =21p^2-14pm-15yp+10ym$

$-27nx-20p^2+45np+12px=(12px-27nx)-(20p^2-45np)= \ =3x(4p-9n)-5p(4p-9n)=(3x-5p)(4p-9n)= \ =3x*4p+3x*(-9n)-5p*4p-5p*(-9n)= \ =12xp-27xn-20p^2+45pn$

Answer 2

фухххх))))

Answer 3

C облегчением)))

Answer 4

Спасибки)