One by one, one by one, one by one. Suppose you want to calculate the product of two digits of A and B, and record the ten digits of A as A and the single digits as C; Write down that the ten digits of b are b and the single digits are d.
Advanced thread-end multiplication, that is, A times B. Record the ten digits and single digits of the result as P and Q respectively. Then carry out the tail-adding operation, that is, C plus D, and record the single digits of the result as R. Finally, multiply the tail by the tail, that is, C times D, and record the single digits of the result as S.
The final product can be obtained by combining P, Q, R and S into a four-digit number. The thousands and hundreds of this four-digit number are P, the ten digits are q+r (if q+r is greater than or equal to 10, you need to carry it), and the single digit is S.
For example, calculate the product of 47 and 38. According to the formula, first multiply the head to get 14 (i.e. 4×3= 12, p= 1, q=2), and then add the tail to get 15 (i.e. 7+8= 15, r =). The combination results in 1456, so 47×38= 1456.
Function of multiplication formula:
1, the multiplication formula laid the foundation for learning multiplication. By reciting the multiplication formula, let the children master the basic multiplication calculation rules and understand the basic concepts of multiplication. This is very important for their subsequent mathematics study, because only by mastering the basic multiplication operation can they further learn more complex mathematical concepts and skills.
2. Multiplication formula can improve the calculation speed. In our daily life, we often need to make quick mathematical calculations. People who are proficient in multiplication formulas can complete multiplication in a short time, thus improving the calculation efficiency. This is very helpful for solving practical problems and making quick decisions.
3. The multiplication formula also helps to cultivate logical thinking and mathematical ability. By learning multiplication formula, people can exercise their logical thinking and reasoning ability, and cultivate their mathematical thinking and problem-solving ability. These abilities are very important for the all-round development of individuals and are widely used in academic, professional and daily life.