Q. Subtract.The numerator should be expanded and simplified. The denominator should be either expanded or factored.x2−3x−182x−x2+6x+95=
Factor the denominators: First, we need to factor the denominators of both fractions to see if they can be simplified or if there are any common factors.The first denominator is x2−3x−18. We look for two numbers that multiply to −18 and add to −3. These numbers are −6 and +3.So, x2−3x−18 factors to (x−6)(x+3).
Factor the first denominator: The second denominator is x2+6x+9. We look for two numbers that multiply to 9 and add to 6. These numbers are +3 and +3. So, x2+6x+9 factors to (x+3)(x+3) or (x+3)2.
Factor the second denominator: Now we rewrite the original expression with the factored denominators: (2x)/((x−6)(x+3))−(5)/((x+3)2).
Rewrite the expression with factored denominators: To subtract these fractions, we need a common denominator. The least common denominator (LCD) is (x−6)(x+3)2.We need to multiply the numerator and denominator of the first fraction by (x+3) to have the LCD as the denominator.
Find the least common denominator: After multiplying, the first fraction becomes (2x×(x+3))/((x−6)(x+3)2). We expand the numerator: 2x×(x+3)=2x2+6x. So the first fraction is now (2x2+6x)/((x−6)(x+3)2).
Multiply the numerator and denominator of the first fraction: The second fraction already has (x+3)2 in the denominator, so we only need to multiply the numerator and denominator by (x−6) to have the LCD as the denominator.
Expand the numerator of the first fraction: After multiplying, the second fraction becomes (5×(x−6))/((x+3)2×(x−6)). We expand the numerator: 5×(x−6)=5x−30. So the second fraction is now (5x−30)/((x+3)2×(x−6)).
Multiply the numerator and denominator of the second fraction: Now we can subtract the two fractions since they have the same denominator: egin{equation}\frac{2x^2 + 6x}{(x - 6)(x + 3)^2} - \frac{5x - 30}{(x - 6)(x + 3)^2}.\end{equation}
Expand the numerator of the second fraction: Subtracting the numerators gives us: (2x2+6x)−(5x−30).We distribute the negative sign through the second expression: −5x+30.Now we combine like terms: 2x2+6x−5x+30.
Subtract the two fractions: Combining like terms, we get: 2x2+x+30. So the combined numerator is 2x2+x+30.
Subtract the numerators: The final simplified expression is: egin{equation}\frac{2x^2 + x + 30}{(x - 6)(x + 3)^2}.\end{equation}
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