$$\frac{x+1}{4}$$  

$$\frac{4}{x+1}$$  

$$\frac{x-1}{4}$$  

$$\frac{4}{x-1}$$  

$$\frac{5}{x+2}$$  

$$5\left(x+2\right)$$  

$$\frac{1}{5\left(x+2\right)}$$  

$$\frac{x+2}{5}$$  

$$\frac{6\left(x-1\right)}{\left(x+3\right)\left(x-3\right)}$$  

$$\frac{-6\left(x-1\right)}{\left(x+3\right)\left(x-3\right)}$$  

$$\frac{6\left(x+1\right)}{\left(x+3\right)\left(x-3\right)}$$  

$$\frac{-6\left(x+1\right)}{\left(x+3\right)\left(x-3\right)}$$  

$$\frac{1}{2}$$  

$$2$$  

$$\frac{2}{x}$$  

$$\frac{2m+3}{2}$$  

$$\frac{3y+7}{8y^2}$$  

$$\frac{-8y^2}{3y-7}$$  

$$\frac{3y-7}{8y^2}$$  

$$\frac{8y^2}{3y-7}$$  

$$\frac{21y^2-20x^2}{72x^4y^3}$$  

$$\frac{21x^2-20y^2}{72x^4y^3}$$  

$$\frac{21y^2+20x^2}{72x^4y^3}$$  

$$\frac{21x^2+20y^2}{72x^4y^3}$$