SET THEORY and VENN DIAGRAMS T Bolan

Words used to describe Automobiles Cars Motorcycles Trucks 4-wheelers 2-wheelers 18-wheelers 3-wheelers Ford MitsubishiFarrari 2-door 4-door vans Old new gas diesel Solar green red blue

We can use these words to categorize cars into types Cars Motorcycles Trucks 4-wheelers 2-wheelers 18-wheelers 3-wheelers Ford MitsubishiFarrari 2-door 4-door vans Old new gas diesel Solar green red blue

Now, pretend for a second that this box, represents “Crazy Bob’s Autos” parking lot. And everyone sold their car to Crazy Bob So he has every car in existence, Every car in existence motorcycles 18-wheelers Blue cars

1.Where do I go to find a motorcycle? Where do I Find an 18-wheeler? 3.Where do I get a Blue car?

Where would I look to find a blue car if I don’t want an 18-wheeler? Where would I look to find a blue car if I don’t want an 18-wheeler or a motorcycle? What about if I want a motorcycle but not a blue one?

What If I don’t care what I buy, as long as it isn’t blue?

These are pretty easy it actually takes longer to read the question than it does to answer it. Let’s simplify this

The symbol means INTERSECTION It means both. If you want a blue motorcycle, Then you want blue and motorcycle

The symbol means UNION It means either. If you want any Motorcycle OR Anything Blue

What does this look like?

They don’t overlap. There is no such thing Here we are asked for a Motorcycle that is also an 18-wheeler When there is no answer, We call it the EMPTY SET Or NULL SET

Before we go any further, let’s make sure we understand the NULL SET. It is not the same as zero. How many donkeys have walked on the moon? 0 How many donkeys should you eat to turn your hair purple? Zero donkeys is not the right answer. This question has no answer. Something is wrong with the question. NULL SET

If we draw a bar above it. It means the opposite. “I want a motorcycle or an 18-wheeler” “Anything but motorcycle or an 18-wheeler”

“I want an 18-wheeler” “Anything but an 18-wheeler”

“I want a blue motorcycle” “Anything but a blue motorcycle”

“I don’t care what I get, as long as it isn’t blue”

In the box is every student in the school. M for kids in your MATH class S for kids in your SCIENCE class G for kids in your GYM class

Students in Math OR ScienceStudents in Math AND Science Students in Math AND Science AND Gym Students NOT in Gym or Math

Students NOT in Gym AND Math In other words: you start to tell a joke in math class, but the bell rings And you have to finish it in gym. Who DOESN’T get the joke? These guys heard the whole joke Sooo everyone else