Set notation
Okay kiddo, let’s talk about set notation. So, imagine you have a big toy box with all of your toys inside. That toy box is like a set, which is just a collection of things or objects. Set notation is a way to talk about or describe that set.
In set notation, we use braces { } to show that we are talking about a set. Inside the braces, we list all of the things, or elements, that are in that set. For example, if we have a set of all the chocolate candies you like, we can write it like this: { Kit-Kat, Snickers, Reese’s, M&Ms }.
We can also use symbols to show if something is in a set or not. The symbol ∉ (which kind of looks like a little man with a hat) means "not in the set." For example, if you don’t like Milky Way bars, we can write it like this: Milky Way ∉ { Kit-Kat, Snickers, Reese’s, M&Ms }.
Another symbol we use is the intersection symbol, which looks like an upside-down letter "U." This symbol means that two sets have elements in common. So, if we have one set of all the fruits you like and another set of all the fruits your friend likes, we can use the intersection symbol to show which fruits you both like. If your set is { apple, banana, strawberry } and your friend’s set is { strawberry, orange, pineapple }, the intersection of both sets would be { strawberry }.
Lastly, we can use the union symbol, which looks like a letter "U." This symbol means we are combining two sets into one set. For example, if you have a set of all the toys you have and another set of all the presents you’ve received, we can use the union symbol to make a new set of all your possessions. If your toy set is { legos, teddy bear, action figures } and your presents set is { bike, dollhouse, soccer ball }, the union of both sets would be { legos, teddy bear, action figures, bike, dollhouse, soccer ball }.
So there you have it, kiddo, a simple explanation of set notation!
In set notation, we use braces { } to show that we are talking about a set. Inside the braces, we list all of the things, or elements, that are in that set. For example, if we have a set of all the chocolate candies you like, we can write it like this: { Kit-Kat, Snickers, Reese’s, M&Ms }.
We can also use symbols to show if something is in a set or not. The symbol ∉ (which kind of looks like a little man with a hat) means "not in the set." For example, if you don’t like Milky Way bars, we can write it like this: Milky Way ∉ { Kit-Kat, Snickers, Reese’s, M&Ms }.
Another symbol we use is the intersection symbol, which looks like an upside-down letter "U." This symbol means that two sets have elements in common. So, if we have one set of all the fruits you like and another set of all the fruits your friend likes, we can use the intersection symbol to show which fruits you both like. If your set is { apple, banana, strawberry } and your friend’s set is { strawberry, orange, pineapple }, the intersection of both sets would be { strawberry }.
Lastly, we can use the union symbol, which looks like a letter "U." This symbol means we are combining two sets into one set. For example, if you have a set of all the toys you have and another set of all the presents you’ve received, we can use the union symbol to make a new set of all your possessions. If your toy set is { legos, teddy bear, action figures } and your presents set is { bike, dollhouse, soccer ball }, the union of both sets would be { legos, teddy bear, action figures, bike, dollhouse, soccer ball }.
So there you have it, kiddo, a simple explanation of set notation!