Like equation x? -5x+6 = 0, and the root of this equation (the solution of the unary equation is also called the root, as you all know) is 2 and 3, or 2 or 3.
Because it is scientific. You think, if the unknown x is replaced by 2 or 3, the equation will be established immediately.
This is not the same as spoken English in life. I guess that's what you're struggling with.
This involves the NAND gate of the physical electronic circuit.
After studying for a month or two, I gradually know what's going on. Don't worry now.
∨ Called "Alliance" symbol. Also known as "or set symbols". ∩, known as "cross", also known as "rush".
Just look at the examples in the textbook.