Answer
A ∩ C = {1,3,4}
Work Step by Step
A ∩ C
∩ means intersect when talking about sets.
A ∩ C means to find the intersection of the elements of set A and set C. By intersection we mean those elements that are in both sets A and B. The elements must be in both sets to be in the intersection.
A={1,3,4,5,9}
C={1,3,4,6}
You can find the intersection by comparing each element in A with each element in C.
1 is in A, is it in C? Yes, so keep it. 3 and 4 are also in C, so they are also in the intersection. The last 2 elements, 5 and 9, are not in C so they can be dropped.
The intersection of A and C then is {1,3,4}.
