Question

Does anyone have or know of a trick or something that I can use to remember that, in equations and inequalities, 'or' means union and 'and' means intersection? I'm always confusing these.

Answer 1

Do you mean the symbols themselves?
\[A\cap B, A\cup B\]

Answer 2

well if you think about them not as equations but as *sets*, it might make a little more sense. I'm sure you're familiar with venn diagrams? ...

Answer 3

if we want something in A or B, then we can take anything in either circle. If we want something in both A AND B, then we can only take things from the overlapping region in the middle.

Answer 4

no tricks needed. :p

Answer 5

:) thanks