Maths Dictionary · SS 1
Intersection (∩)
Simple meaning
The elements that are in BOTH sets: the overlap in a Venn diagram.
Example
If A = {1, 2, 3} and B = {2, 3, 4}, then A ∩ B = {2, 3}.
See it
From the Venn Diagrams lesson. Try moving things around.
n(J)15 + 10 = 25
n(F)8 + 10 = 18
n(J ∩ F)10
n(J ∪ F)25 + 18 − 10 = 33
n(J′)8 + 7 = 15
n(ξ)40