Questions: Give the partial fraction decomposition for the following function.
20x-7/x^2-x
20x-7/x^2-x=
Transcript text: Give the partial fraction decomposition for the following function.
\[
\begin{array}{l}
\frac{20 x-7}{x^{2}-x} \\
\frac{20 x-7}{x^{2}-x}=
\end{array}
\]
Solution
Solution Steps
To find the partial fraction decomposition, first factor the denominator. Then, express the fraction as a sum of simpler fractions with unknown coefficients. Finally, solve for these coefficients by equating and simplifying.
Step 1: Factor the Denominator
The given function is \(\frac{20x - 7}{x^2 - x}\). First, factor the denominator:
\[ x^2 - x = x(x - 1) \]
Step 2: Set Up Partial Fractions
Express the fraction as a sum of simpler fractions:
\[ \frac{20x - 7}{x(x - 1)} = \frac{A}{x} + \frac{B}{x - 1} \]
Step 3: Solve for Coefficients
Multiply through by the common denominator \(x(x - 1)\) to clear the fractions:
\[ 20x - 7 = A(x - 1) + Bx \]
Expand and collect like terms:
\[ 20x - 7 = Ax - A + Bx \]
\[ 20x - 7 = (A + B)x - A \]
Equate coefficients:
\( A + B = 20 \)
\(-A = -7\)
From equation 2, solve for \(A\):
\[ A = 7 \]
Substitute \(A = 7\) into equation 1:
\[ 7 + B = 20 \]
\[ B = 13 \]
Step 4: Write the Decomposition
Substitute \(A\) and \(B\) back into the partial fractions:
\[ \frac{20x - 7}{x(x - 1)} = \frac{7}{x} + \frac{13}{x - 1} \]
Final Answer
The partial fraction decomposition is:
\[
\boxed{\frac{7}{x} + \frac{13}{x - 1}}
\]