Precalculus (6th Edition)

Published by Pearson
ISBN 10: 013421742X
ISBN 13: 978-0-13421-742-0

Chapter 9 - Systems and Matrices - Test - Page 957: 14

Answer

$\frac{2}{x+3}+\frac{7}{x-1}$

Work Step by Step

1. Factor the denominator as $x^2+2x-3=(x+3)(x-1)$ 2. Assume $\frac{9x+19}{x^2+2x-3}=\frac{A}{x+3}+\frac{B}{x-1}$ 3. Evaluate the right side, we have $RHS=\frac{Ax-A+Bx+3B}{x^2+2x-3}=\frac{(A+B)x-A+3B}{x^2+2x-3}$ 4. Compare the above with the left hand side to get $\begin{cases} A+B=9 \\ -A+3B=19 \end{cases}$ 5. Add the two equations to get $4B=28$, thus $B=7$ and $A=9-B=2$ 6. The partial fraction decomposition is $\frac{9x+19}{x^2+2x-3}=\frac{2}{x+3}+\frac{7}{x-1}$
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.