b. \( \frac{2}{2 x-4}-\frac{5}{x^{2}-4} \)

Calculate or simplify the expression \( \frac{2}{2x-4}-\frac{5}{x^{2}-4} \). Simplify the expression by following steps: - step0: Solution: \(\frac{2}{2x-4}-\frac{5}{x^{2}-4}\) - step1: Reduce the fraction: \(\frac{1}{x-2}-\frac{5}{x^{2}-4}\) - step2: Factor the expression: \(\frac{1}{x-2}-\frac{5}{\left(x+2\right)\left(x-2\right)}\) - step3: Reduce fractions to a common denominator: \(\frac{x+2}{\left(x-2\right)\left(x+2\right)}-\frac{5}{\left(x+2\right)\left(x-2\right)}\) - step4: Rewrite the expression: \(\frac{x+2}{\left(x+2\right)\left(x-2\right)}-\frac{5}{\left(x+2\right)\left(x-2\right)}\) - step5: Transform the expression: \(\frac{x+2-5}{\left(x+2\right)\left(x-2\right)}\) - step6: Subtract the numbers: \(\frac{x-3}{\left(x+2\right)\left(x-2\right)}\) - step7: Multiply the terms: \(\frac{x-3}{x^{2}-4}\) The simplified form of the expression \( \frac{2}{2x-4}-\frac{5}{x^{2}-4} \) is \( \frac{x-3}{x^{2}-4} \).