Question

Tính:

\(P=x^3+x^2y-2x^2-xy-y^2+3y+x+2017\)biết x + y = 2

Answer 1

\(P=x^3+x^2y-2x^2-xy-y^2+3y+x+2017\)

\(P=x^2\left(x+y\right)-2x^2-xy-y^2+3y+x+2017\)

\(P=2x^2-2x^2-xy-y^2+3y+x+2017\)

\(P=-xy-y^2+3y+x+2017\)

\(P=-y\left(x+y\right)+3y+x+2017\)

\(P=-2y+3y+x+2017\)

\(P=x+y+2017\)

\(P=2+2017=2019\)

Answer 2

P=x²(x+y)-2x²-y(y+x)+3y+x+2017

P=2x²-2x²-2y+3y+x+2017

P=2019