Constant equals sign is generally used when some parameter variables are constants or constant expressions, which always indicates that the relationship has nothing to do with the variables. For example, the function f(x)≡k means that no matter what the value of x is, the value of this function is always k.

2. All equal signs

If △ABC is all equal to △A'B'C, it can be expressed as △ABC≠△A' b' c' (it can also be expressed as "").

3, equivalent to a number

Let p and q be two propositions. If pq is always true, it is said that P and Q are logically equivalent and marked as P ≡ Q. ..

4. Congruence symbol

Let m be a positive integer greater than 1, and A and B are integers. If m|(a-b), A and B are said to be congruent with the module M, and the module M is expressed as a≡b(mod m) and is expressed as congruence with the module M of B. ..

Extended data

/kloc-in the 6th century, the French mathematician Viette used "=" to indicate the difference between two quantities. However, Calder, a professor of mathematics and rhetoric at Oxford University in England, thinks that it is most appropriate to use two parallel and equal straight lines to indicate that two numbers are equal, so the equal sign "=" has been used since 1540.

159 1 year, the French mathematician Veda used this symbol in a large number of diamonds, and it was gradually accepted by people. /kloc-In the 7th century, Leibniz in Germany widely used the symbol "=", and he also used "∽" to indicate similarity and ""to indicate congruence in geometry.

Greater than sign ">" and less than sign "

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