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Explain like I’m 5: disjunction operator

Okay, so you know how sometimes we ask questions that can have a yes or no answer? In math, we can use special symbols called “logical operators” to combine those yes or no answers to make new statements. One of those symbols is “or”, which we write as “𝘰𝘳”. It means that if at least one of the statements is true, then the whole statement is true.

Now, let’s say we have two statements: “It rained today” and “It was cloudy yesterday”. We can use the “or” symbol to combine them like this: “It rained today or it was cloudy yesterday”. We can write it like this: (𝘙 ∨ 𝘊), where 𝘙 stands for “It rained today” and 𝘊 stands for “It was cloudy yesterday”.

But what if we know for sure that it didn’t rain today? Then, the statement “It rained today or it was cloudy yesterday” would be true even if it was only cloudy yesterday. So, the truth value of (𝘙 ∨ 𝘊) would be true, even though it didn’t rain today.