[tex] \\ a) \:\ E_{(x)} = \frac{x^2-4}{x^2-4x+4}= \frac{\left(x+2\right)\left(x-2\right)}{x^2-4x+4} = \frac{\left(x+2\right)\left(x-2\right)}{\left(x-2\right)^2} = \boxed{\frac{x+2}{x-2}}
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\\ b) \:\ E_{(x)} + F_{(x)} =>\frac{x+2}{x-2} + \frac{3x+5}{x-2} =\frac{x+2+3x+5}{x-2} = \boxed{\frac{4x+7}{x-2}} [/tex]
