Question

Найдите x^4y-xy^4,если x-y=5
                                     x*y=3

Answer 1

$x^4y-xy^4=xy(x^3-y^3)=\\xy(x-y)(x^2+xy+y^2)=xy(x-y)((x-y)^2+3xy)=\\3*5*(5^2+3*3)=15*(25+9)=510$