Question

1. Выразите выражение : x(1+y)-y(xy-1)-x²y   через p и q если x+y= -p и xy=q

Answer 1

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Answer 2

$x(1+y)-y(xy-1)- x^{2} y=x+xy-x y^{2} +y- x^{2} y=\ x+xy+y-xy(y+x)=\ x+y+xy-xy(x+y)=-p+q-q(-p)=-p+q+qp=q-p+qp$