Question

1:áp dụng quy tắc đối đầu hay thực hiện phép tính cộng

2x+1/2x2-x + 32x2/1-4x2 +1-2x/2x2+x

2:tính

a,4x2/x-2 +3/x-2 +19/2-x

b,2x/x2+2xy +y/xy-2y2 +4/x2-4y2

 

 

Answer 1

Bài 2: 

a: \(=\dfrac{4x^2+3-19}{x-2}=\dfrac{4x^2-16}{x-2}=\dfrac{4\left(x-2\right)\left(x+2\right)}{x-2}=4x+8\)

b: \(=\dfrac{2x}{x^2+2xy}+\dfrac{y}{xy-2y^2}+\dfrac{4}{x^2-4y^2}\)

\(=\dfrac{2}{x+2y}-\dfrac{1}{x-2y}+\dfrac{4}{\left(x-2y\right)\left(x+2y\right)}\)

\(=\dfrac{2x-4y-x-2y+4}{\left(x+2y\right)\left(x-2y\right)}\)

\(=\dfrac{x-6y+4}{\left(x+2y\right)\left(x-2y\right)}\)