Укажите число, обратное разности чисел \(\displaystyle a\) и \(\displaystyle b{\small.}\)

• \(\displaystyle \frac{1}{a-b}\)
• \(\displaystyle -(a-b)\)
• \(\displaystyle -\frac{1}{a-b}\)
• \(\displaystyle \frac{a}{b}-\frac{b}{a}\)