See the attached image.
We start this problem by finding the union of [tex]A[/tex] and [tex]B[/tex]. This is highlighted in green in the attachment.
Next, we find the intersection of that area and [tex]C[/tex] (highlighted in yellow). This means we need to find the area where both [tex]A\cup B[/tex] and [tex]C[/tex] are highlighted. This intersection is highlighted in pink and is the final answer.
(Apologies for the image quality.)
