a: \(=\dfrac{x\cdot5}{x\cdot2xy}=\dfrac{5}{2xy}\)
b: \(=\dfrac{3x^2y^2\cdot5x}{3x^2y^2\cdot4y^3}=\dfrac{5x}{4y^3}\)
c: \(=\dfrac{5x\left(x+2\right)^2\cdot5\left(x+2\right)^3}{5x\left(x+2\right)^2\cdot x^4\cdot4}=\dfrac{5\left(x+2\right)^3}{4x^4}\)
g: \(=\dfrac{x\left(x+5\right)}{2\left(x+5\right)}=\dfrac{x}{2}\)
h: \(=\dfrac{\left(x+1\right)^2}{\left(x-1\right)\left(x+1\right)}=\dfrac{x+1}{x-1}\)
i: \(=\dfrac{\left(x-3\right)\left(x-1\right)\left(x+1\right)}{x\left(x-3\right)}=\dfrac{x^2-1}{x}\)
k \(=\dfrac{\left(x+3\right)\left(x+4\right)}{\left(x+4\right)\left(x-1\right)}=\dfrac{x+3}{x-1}\)
l) \(\dfrac{x^2+y^2+2xy-1}{x^2-y^2+1+2x}=\dfrac{\left(x+y\right)^2-1}{\left(x+1\right)^2-y^2}\)
\(=\dfrac{\left(x+y+1\right)\cdot\left(x+y-1\right)}{\left(x+1-y\right)\left(x+1+y\right)}=\dfrac{x+y-1}{x-y+1}\)
