Answer:
4th option
Step-by-step explanation:
Given
[tex]\frac{x}{x^2+3x+2}[/tex] - [tex]\frac{1}{(x+2)(x+1)}[/tex] ← expand denominator using FOIL
= [tex]\frac{x}{x^2+3x+2}[/tex] - [tex]\frac{1}{x^2+3x+2}[/tex]
Since the denominators are common, then subtract the numerators
= [tex]\frac{x-1}{x^2+3x+2}[/tex]
