Question

- Phân tích thành nhân tử: A, 2x+2y-x^2-xy. B, 4x^3+9x^2-19x-30

Answer 1

\(a,2x+2y-x^2-xy=2x+2y-\left(x^2+xy\right).\)

\(=2\left(x+y\right)-x\left(x+y\right)\)

\(=\left(2-x\right)\left(x+y\right)\)

Answer 2

\(a,2x+2y-x^2-xy=2.\left(x+y\right)-x.\left(x+y\right)=\left(2-x\right).\left(x+y\right)\)

\(b,4x^3+9x^2-19x-30=3x^3+x^3+9x^2-9x-10x-30\)

\(=3x^2.\left(x+3\right)+x.\left(x-3\right).\left(x+3\right)-10.\left(x+3\right)=\left(x+3\right).\left(3x^2+x^2-3x-10\right)\)