Câu hỏi của Vy Nguyễn Đặng Khánh

Question

Q-($2x^4-3x^2y^2+5x^2y-4x+2$)= $2x^2y^2+5x-7y-x^2y$

Vũ Huỳnh Pha Lê · Accepted Answer

$Q-\left(2x^4-3x^2y^2+5x^2y-4x+2\right)=2x^2y^2+5x-7x-x^2y$

$\Rightarrow Q=\left(2x^2y^2+5x-7x-x^2y\right)+\left(2x^4-3x^2y^2+5x^2y-4x+2\right)$

$\Rightarrow Q=2x^2y^2+5x-7x-x^2y+2x^4-3x^2y^2+5x^2y-4x+2$

$\Rightarrow Q=\left(2x^2y^2-3x^2y^2\right)+\left(5x-7x-4x\right)+\left(-x^2y+5x^2y\right)+2x^4+2$

$\Rightarrow Q=-x^2y^2+\left(-6x\right)+4x^2y+2x^4+2$Câu trả lời: $Q-\left(2x^4-3x^2y^2+5x^2y-4x+2\right)=2x^2y^2+5x-7x-x^2y$

$\Rightarrow Q=\left(2x^2y^2+5x-7x-x^2y\right)+\left(2x^4-3x^2y^2+5x^2y-4x+2\right)$

$\Rightarrow Q=2x^2y^2+5x-7x-x^2y+2x^4-3x^2y^2+5x^2y-4x+2$

$\Rightarrow Q=\left(2x^2y^2-3x^2y^2\right)+\left(5x-7x-4x\right)+\left(-x^2y+5x^2y\right)+2x^4+2$

$\Rightarrow Q=-x^2y^2+\left(-6x\right)+4x^2y+2x^4+2$

Bài 6: Cộng, trừ đa thức