Who is the inventor? – + x ÷

The mathematical symbols for addition, subtraction, multiplication, and division were not all invented by a single person at the same time. They were introduced by various scholars over the course of a few centuries.

Here is an overview of who created what:

+ (Plus) and – (Minus)

• Who: Johannes Widmann (a German mathematician)
• When: 1489
• Details: They first appeared in print in his book Mercantile Arithmetic. Originally, they were used in trade to indicate a surplus (+) or a deficit (-) of goods. Only later did they become official mathematical symbols.

× (Multiplication)

• Who: William Oughtred (an English mathematician and clergyman)
• When: 1631
• Details: He introduced the St. Andrew’s cross (×) in his work Clavis Mathematicae.
• Fun fact: The famous scholar Gottfried Wilhelm Leibniz disliked this symbol because it looked too much like the letter x. Therefore, in 1698, he proposed using a dot (·) for multiplication, which is still the standard in higher mathematics today.

÷ (Division)

• Who: Johann Rahn (a Swiss mathematician)
• When: 1659
• Details: Rahn used this symbol (known as the obelus) for the first time in his book Teutsche Algebra.
• Note: In modern mathematics and computer science, the division sign is often replaced by a forward slash (/), which was popularized as early as 1718 by John Rowe.

In summary: