The symbol "∴" is often used in math problems, usually in the process of solving problems;

Easy to remember; The above two points are "because"; The following two points are "so"; ∫ [Because] ∴ [So] is the most commonly used problem in geometry proof;

Be sure to remember: you can't use ∵ directly in the title instead of ∵.

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Ryan was the first person to express "there" with symbols. In an algebra book 1659, he used two symbols "∴" and "⊙" to mean "so", among which "∴" was used more. The English version of the book 1668 also uses these two symbols to mean "so", but "∵" is used more. Jones uses ∴ in 1706 to mean "so". By the middle of18th century, "∵" was used to mean "so", at least as much as "∴". "

By 1827, Euclid's Elements of Geometry published by Cambridge University used ⊙ for "because" and ∴ for "so" respectively. This usage has become more and more popular and has been used ever since.