a.\(=\frac{x}{x-y}+\frac{y}{x-y}+1=\frac{x+y+x-y}{x-y}=\frac{2x}{x-y}\)
b. \(=\frac{4}{x+2}+\frac{3}{x-2}-\frac{5x+2}{\left(x-2\right).\left(x+2\right)}\)
\(=\frac{4x-8+3x+6-5x-2}{\left(x-2\right).\left(x+2\right)}\)
\(=\frac{2x-4}{\left(x-2\right).\left(x+2\right)}=\frac{2.\left(x-2\right)}{\left(x-2\right).\left(x+2\right)}=\frac{2}{x+2}\)
k mik nhé. tks bạn nhiều
a)\(\frac{x}{x-y}-\frac{y}{y-x}+1=\frac{x}{x-y}-\frac{y}{-\left(x-y\right)}+1=\frac{x+y}{x-y}+1=\frac{2x}{x+y}\)
b)\(\frac{4}{x+2}-\frac{3}{2-x}+\frac{5x+2}{4-x^2}=\frac{7}{x+2}-\frac{5x+2}{\left(x-2\right)\left(x+2\right)}=\frac{2x-2}{\left(x-2\right)\left(x+2\right)}\)
