Simplify the expression $\frac{(x^2+5x+4)(x-1)}{(x^2-1)}$.

AlgebraAlgebraic SimplificationPolynomialsFactorizationRational Expressions
2025/3/17

1. Problem Description

Simplify the expression (x2+5x+4)(x1)(x21)\frac{(x^2+5x+4)(x-1)}{(x^2-1)}.

2. Solution Steps

First, factor the quadratic expression x2+5x+4x^2 + 5x + 4. We are looking for two numbers that multiply to 4 and add to

5. These numbers are 1 and

4. Therefore, $x^2 + 5x + 4 = (x+1)(x+4)$.

Next, factor the difference of squares x21x^2-1. This is x212=(x1)(x+1)x^2 - 1^2 = (x-1)(x+1).
Now, substitute the factored expressions into the original expression:
(x2+5x+4)(x1)(x21)=(x+1)(x+4)(x1)(x1)(x+1)\frac{(x^2+5x+4)(x-1)}{(x^2-1)} = \frac{(x+1)(x+4)(x-1)}{(x-1)(x+1)}.
We can cancel the common factors (x+1)(x+1) and (x1)(x-1) from the numerator and denominator, provided x1x \ne 1 and x1x \ne -1:
(x+1)(x+4)(x1)(x1)(x+1)=x+4\frac{(x+1)(x+4)(x-1)}{(x-1)(x+1)} = x+4.

3. Final Answer

x+4x+4