关于等式右侧集合运算组合符号含义的咨询

Hey, I feel you completely! I’ve been there too—union and intersection are straightforward when they’re alone, but throw ’em together in a single expression, and suddenly your brain goes “wait, what order do I even process this in?”

Let me break down the common confusing scenarios to clear things up:

• If you’re looking at a chained expression like A ∩ B ∪ C, remember that intersection takes precedence over union (similar to how multiplication comes before addition in basic math). You’ll first calculate the intersection of sets A and B, then take the union of that resulting set with C.
• If parentheses are involved, like (A ∪ B) ∩ C, always follow the parentheses first: compute the union of A and B first, then find the intersection of that result with C.
• For more complex nested combinations, stick to the same rules: parentheses dictate the first steps, then handle intersections before unions.

If you can share the specific combined expression that’s confusing you, I can walk through it step by step to make it crystal clear!

备注：内容来源于stack exchange，提问作者John van Zalk