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Write it in reduced form as a ratio of polynomials p(x)/q(x)

Write it in reduced form as a ratio of polynomials p(x)/q(x)-example-1
User KQS
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1 Answer

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We are given the following expression


(x^2)/(x-5)-(8)/(x-2)

Let us re-write the expression as a ratio of polynomials p(x)/q(x)

First of all, find the least common multiple (LCM) of the denominators.

The LCM of the denominators is given by


(x-5)(x-2)

Now, adjust the fractions based on the LCM


\begin{gathered} (x^2)/(x-5)*((x-2))/((x-2))=(x^2(x-2))/((x-5)(x-2)) \\ \frac{8^{}}{x-2}*((x-5))/((x-5))=(8(x-5))/((x-2)(x-5)) \end{gathered}

So, the expression becomes


(x^2(x-2))/((x-5)(x-2))-(8(x-5))/((x-2)(x-5))

Now, apply the fraction rule


(a)/(c)-(b)/(c)=(a-b)/(c)
(x^2(x-2))/((x-5)(x-2))-(8(x-5))/((x-2)(x-5))=(x^2(x-2)-8(x-5))/((x-5)(x-2))

Finally, expand the products in the numerator


(x^2(x-2)-8(x-5))/((x-5)(x-2))=(x^3-2x^2-8x+40)/((x-5)(x-2))

Therefore, the given expression as a ratio of polynomials p(x)/q(x) is


(x^3-2x^2-8x+40)/((x-5)(x-2))

User Lena Bru
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