Simplifying Rational Expressions Math Example 3

Follow the full solution, then compare it with the other examples linked below.

Example 3

easy
Simplify x2โˆ’4x+2\frac{x^2 - 4}{x + 2}.

Solution

  1. 1
    Factor: (x+2)(xโˆ’2)x+2=xโˆ’2\frac{(x+2)(x-2)}{x+2} = x - 2, xโ‰ โˆ’2x \neq -2.
  2. 2
    Check: At x=3x = 3: 9โˆ’45=1\frac{9-4}{5} = 1 and 3โˆ’2=13-2 = 1 โœ“

Answer

xโˆ’2x - 2, xโ‰ โˆ’2x \neq -2
Recognizing the numerator as a difference of squares is key. After factoring, the (x+2)(x+2) cancels with the denominator.

About Simplifying Rational Expressions

Simplifying a rational expression p(x)q(x)\frac{p(x)}{q(x)} by factoring both the numerator and denominator, then canceling common factors. The domain must exclude values that make any original denominator zero.

Learn more about Simplifying Rational Expressions โ†’

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