Beginner
Discrete Mathematics & Math
Q30 / 100
What is the principle of inclusion-exclusion?
Correct! Well done.
Incorrect.
The correct answer is B) A counting formula: |A∪B| = |A| + |B| - |A∩B|, generalized to n sets by alternately adding and subtracting intersections
B
Correct Answer
A counting formula: |A∪B| = |A| + |B| - |A∩B|, generalized to n sets by alternately adding and subtracting intersections
Explanation
|A∪B∪C| = |A|+|B|+|C| - |A∩B| - |A∩C| - |B∩C| + |A∩B∩C|. Avoids double-counting. Applications: counting derangements, the sieve of Eratosthenes, scheduling conflicts.
Progress
30/100