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Simplify the expression given below. x+2/X^3+2x^2-9x-18 divided by 3x +1/x^2-9

1 Answer

5 votes
Answer:


(1)/(3x+1)


Step-by-step explanation:

1) Expression given:


( (x+2)/(x^3+2x^2-9x-18) )/( (3x+1)/(x^2-9) )

2) Factor the denominator of the first fraction:


x^3+2x^2-9x-18=(x^3+2x^2)-(9x+18)=x^2(x+2)-9(x+2)=


(x+2)(x^2-9)

3) Rewrite the expression


( (x+2)/((x+2)(x^2-9)) )/( (3x+1)/(x^2-9) )

4) In the upper fraction x+2 in the numerator cancels out with x + 2 in the denominator.


( (1)/(x^2-9) )/( (3x+1)/(x^2-9) )

5) x² - 9 in both denominators cancel out each other, and the final result is:


(1)/(3x+1)
User Mitch Dempsey
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