The history of multiplication can be traced back to ancient India. In Indian mathematics, multiplication was originally expressed by addition, because there was no special multiplication symbol at that time. For example, to represent the product of two numbers A and B, you can use A plus your own b times, that is, A+(A+A+A)+…+(A+A+…+A) (* * B A). Later, Indian mathematician Ayepihite invented a new method to express the product, which is the multiplication symbol × which we use now.
The shape of the symbol x consists of two horizontal lines || In Ayepihite's works, these two horizontal lines represent the weight of the left and right sides of a balance, while the middle point represents the unknown. This symbol was originally used to represent the product of unknown x and known a, which is ax. With the passage of time, this symbol gradually became widely used, and finally evolved into the multiplication sign we use today.
In China, the multiplication symbol x was originally called the difference sign, because it is a combination of minus sign and plus sign. /kloc-In the middle of 0/9th century, with the spread of western mathematics in China, the multiplication sign × was also introduced to China. Now, the multiplication sign × has become one of the universal mathematical symbols in the world and is widely used in various mathematical operations.
The application of multiplication symbol in mathematics;
1, multiplication operation: the most basic application of multiplication symbol is multiplication operation. In mathematics, multiplication is one of the most common and basic operations, that is, adding a number repeatedly. For example, 3×4 means that 3 is repeated and added 4 times, and the result is 12. Multiplication can be used to calculate various numerical values, such as fractions, decimals, integers, matrices, etc.
2. Matrix multiplication: In matrix algebra, multiplication symbols are used for matrix multiplication. A matrix is a rectangular array of values. Matrix multiplication is to multiply and sum the values of the corresponding positions of two matrices, and the result is a new matrix. Matrix multiplication is widely used in scientific calculation, engineering technology and economics.
3. Vector multiplication: In vector algebra, multiplication symbols are also used for vector multiplication. Vector is a directional quantity, and vector multiplication includes scalar multiplication and vector multiplication. Scalar multiplication is to multiply a scalar by a vector, and the result is a vector with the same direction as the original vector, while vector multiplication is to multiply two vectors to get a new vector. Vector multiplication is widely used in physics, engineering and machine learning.