●●● ●●●● ●●●●● ●●●● ●●0●● Basic Counting Techniques ●●●0 ●●●● ● Inclusion-Eⅹc| usion formula ●|AUB|=|A+B|-|A∩B ●| AUBUC|=A+B|+c|-|AnB|-|Anc|-|B∩c +|AnB∩c A B A C5 Basic Counting Techniques ⚫ Inclusion-Exclusion Formula: ⚫ |AUB| = |A| + |B| - |A∩B| ⚫ |AUBUC| = |A| + |B| + |C| - |A∩B| - |A∩C| - |B∩C| + |A∩B ∩C| A B C A B