Published
- 1 min read
Question: Perform the indicated operations. \frac{15x}{x-1} - \frac{5}{x+1} - \frac{10}{x^2-1}…
Perform the indicated operations.
\frac{15x}{x-1} - \frac{5}{x+1} - \frac{10}{x^2-1}
\frac{15x}{x-1} - \frac{5}{x+1} - \frac{10}{x^2-1} = \square
(Simplify your answer. Type your answer in factored form.)
Solution
Find a common denominator.
\[ x^2 - 1 = (x - 1)(x + 1) \]
Rewrite each term with the common denominator.
\[ \frac{15x}{x - 1} = \frac{15x(x + 1)}{(x - 1)(x + 1)} \]
\[ \frac{5}{x + 1} = \frac{5(x - 1)}{(x - 1)(x + 1)} \]
\[ \frac{10}{x^2 - 1} = \frac{10}{(x - 1)(x + 1)} \]
Combine the fractions.
\[ \frac{15x(x + 1) - 5(x - 1) - 10}{(x - 1)(x + 1)} \]
Simplify the numerator.
\[ 15x^2 + 15x - 5x + 5 - 10 = 15x^2 + 10x - 5 \]
Factor the numerator.
\[ 5(3x^2 + 2x - 1) = 5(3x - 1)(x + 1) \]
Cancel \((x + 1)\).
\[ \frac{5(3x - 1)}{x - 1} \]
Answer:
\[ \frac{5(3x - 1)}{x - 1} \]