Jinhua whole brain speed calculation
Jinhua whole brain speed calculation is a fast brain calculation technology course developed by simulating computer operation programs, which can enable children to quickly learn to add, subtract, multiply, divide, multiply and check any number. Thereby quickly improving the operation speed and accuracy of children.
the operation principle of Jinhua whole brain quick calculation
the operation principle of Jinhua whole brain quick calculation is to * * the brain through the activities of both hands, so that the brain can directly produce sensitive conditioned reflex to numbers, so it can achieve the purpose of quick calculation.
(1) Take the hand as the operator and generate an intuitive operation process.
(2) The brain is used as a memory to quickly react and express the operation process.
for example: 6752+1629 =?
Example
Operation process and method: the first digit 6+1 is 7, the last digit (7+6) is 1, carry in 1, the first digit 7+1 writes 8, the hundredth digit 7 subtracts 6' s complement 4 to write 3, (the last digit is less than 1 because of 5+2, and the standard does not carry), and the tenth digit 5+2 is 7, and the last digit (see 7).
Some principles of Jinhua's whole brain quick calculation multiplication operation
Let A, B, C and D be undetermined numbers, Then the product of any two factors can be expressed as:
AB× CD = (AB+A× D/C )× C+B× D
= AB× C+A× D× C/ C+b× d
= ab× c+a× d× 1+b× d
= ab× c+A× d+b× d
= ab× c+(A+b) × d
= ab× c+ab× d.
the product of two factors can be calculated by this method as long as the first number of the two factors is an integer multiple,
that is, when A =nC, AB×CD=(AB+n D)×C+B×D
For example: < P > 23× 13 = 29× 1+3× 3 = 299 < P > 33× 12 = 39× 1+3× 2 = 396 < P > Wei Dewu. So as to quickly improve the learners' quick calculation ability of oral calculation and mental calculation. 1, quick addition: the method of calculating the quick addition of any number of digits is very simple. Learners only need to memorize a general formula of quick addition-"Standard addition (for decimal digits) minus plus complement, and the previous digit plus one" can completely solve the quick addition method of any number of digits from high to low, such as: (1), 67+48 = (6+5) × 1. 2, fast subtraction: the fast subtraction method for calculating any number of digits is also a general formula for fast subtraction-"standard subtraction (for borrowed digits) plus or minus, and the previous subtraction minus one" can completely solve the fast subtraction method for counting any number of digits from high to low, such as: (1), 67-48 = (6-5) × 1+(7+. 3. Fast multiplication: The general formula of Wei's fast multiplication is ab×cd=(a+1)×c×1+b×d+ Wei's fast transformation number× 1. Fast calculation number |=(a-c)×d+(b+d-1)×c, fast calculation number ‖=(a+b-1)×c+(d-c)×a, fast calculation number ⅲ = a× d-'b' (complement It is unique and unparalleled. (1), with the first fast calculation of the evolution number =(a-c)×d+(b+d-1)×c, it is suitable for arbitrary two-digit multiplication with the same head and tail, such as: 26×28, 47×48, 87× 84-and so on, and its evolution number is clear at a glance, respectively equal to. (2) Using the second fast calculation method, the number of transitions =(a+b-1)×c+(d-c)×a is suitable for any two-digit multiplication in which the sum of two digits of one factor is close to "1" and the difference of two digits of another factor is close to "", such as: 28× 67, 47× 98, 73. (3), using the third kind of speed to calculate the evolution number = a× d-'b' (complement )× c is suitable for the general multiplication speed calculation of the evolution number of any two digits. 4, Wei Dewu's story of quick calculation when he was a child: Wei Dewu was brilliant since childhood, and there were many unknown legends during his primary school. One day, a math teacher didn't know where he learned that Xiao Wei Dewu was very talented in the speed of digital calculation. In order to be confirmed, he personally worked out an arithmetic problem of "1+2+3+4+-+1" and asked Xiao Wei Dewu to work out an accurate answer within half an hour. As a result, it took Xiao Wei Dewu less than 5 minutes to give the correct answer: "55". As soon as the teacher heard it, he was dumbfounded. He couldn't believe that Wei Dewu had such a fast calculation speed. It turned out that Xiao Dewu didn't accumulate one by one according to the traditional method, but took a pen and kept gesticulating on the paper. Finally, the calculated natural numbers of "1+2+3+4+-+1" were arranged in a ladder shape in turn, and then with the help of the trapezoidal area formula S = (a+in primary school. If the first number "1" of "1+2+3+4+-+1" is regarded as the length of the upper and lower sides of the trapezoidal area, the mantissa "1" is regarded as the length of the lower sides of the trapezoidal area, and the added number of "1" is regarded as the height of the trapezoidal area, we can get "1+2+3+" It is said that before Wei Dewu graduated from primary school, under the guidance of the trapezoidal area formula s=(a+b)÷2×h in primary school arithmetic and the basic nature of "equation" in primary school arithmetic, The general formula s={2a1+p(n-1)}÷2×n and arbitrary "equal ratio" sequence (1+3+5+7+----------------------have been successfully derived successively. Mathematical legends like this are numerous for Xiao Wei Dewu.
Special two-digit number multiplied by two-digit number
1. More than ten times more than ten:
Formula: head by head, tail by tail, tail by tail.
Note: Multiply the digits. If there are not enough two digits, use .
2. The heads are the same, and the tails are complementary (the sum of the tails equals 1):
Formula: after adding 1 to a head, the head is multiplied by the head, and the tail is multiplied by the tail.
Note: Multiply the digits. If there are not enough two digits, use .
3. The first multiplier is complementary, and the other multiplier has the same number:
Formula: after a head is added with 1, the head is multiplied by the head and the tail is multiplied by the tail.
Note: Multiply the digits. If there are not enough two digits, use .
4. Multiply dozens of eleven by dozens of eleven:
Formula: head by head, head by head, tail by tail.
5.11 times any number:
formula: the head and tail fall without moving, and the sum in the middle drops down.
note: if you add up to ten, you will get one.
6. Multiply a dozen by any number:
Formula: the first digit of the second multiplier does not fall, and the unit of the first factor is multiplied by each digit after the second factor, and then it falls.
note: if you add up to ten, you will get one.
7. Multiply multiple digits by multiple digits
Formula: the former factor multiplies each digit of the latter factor one by one, the second factor multiplies 1 times, the third factor multiplies 1 times, and so on.
Note: If the sum is full, it will be one.
The fast algorithms of "the first with the last and the tenth" and "the last with the first and the tenth" about the multiplication of two digits in mathematics. The so-called "beginning with the end and ten" means that two numbers are multiplied, and the ten digits are the same, and the sum of the single digits is 1. For example, 67×63, all the ten digits are 6, and the sum of the single digits 7+3 is just equal to 1. I told him that the multiplication of numbers like this is actually regular. That is, the product of the single digits of two numbers is the last two digits of the number, and if it is less than 1, the ten digits are supplemented with ; Take one of the ten digits with the same number and multiply it by 1, and the result is the thousand and hundred digits of the number. Specific to the above example 67×63, 7×3=21, which is the last two digits of the number; 6×(6+1)=6×7=42, which is the first two digits of the number. Taken together, it is 67×63=4221. Similarly, 15×15=225, 89×81=729, 64×66=4224, 92×98=916. After I told him this little secret of quick calculation, the little guy was already a little excited. After "pestering" me to give him all the questions that can be given and all the calculations are correct, he clamored for me to teach him the quick calculation method of "ending with the same head and ten". I told him that the so-called "ending with the same head and ten" is the multiplication of two numbers, and the digits are exactly the same. The sum of ten digits is just 1, for example, 45×65, and both digits are 5. The result of ten digits 4+6 is just equal to 1. Its calculation rule is that the product of the same digits of two numbers is the last two digits of the number, and if it is less than 1, it will be supplemented by on the tenth digit; After multiplying dozens of digits and adding the same single digit, the result is the hundreds and thousands of digits. Specific to the above example, 45×65, 5×5=25, which is the last two digits of the number, and 4×6+5=29, which is the front part of the number, so 45×65=2925. Similarly, 11×91=11, 83×23=199, 74×34=2516, 97×17=1649.
in order to make it easy for everyone to understand the general law of two-digit multiplication, here will be illustrated by specific examples. By comparing a large number of two-digit multiplication results, I divide the two-digit multiplication results into three parts, one digit, ten digits, and more than ten digits, that is, hundreds and thousands. (The maximum multiplication of two digits will not exceed 1,, so it can only reach thousands.) Here's an example: 42× 56 = 2,352
, where the method of determining the single digits of the numerator is to take the mantissa of the product of two digits as the single digits of the numerator. Specific to the above example, 2×6=12, where 2 is the mantissa of the result and 1 is the single digit;
the method of determining the tens of digits of the numerator is to take the sum of the cross multiplication of two digits and ten digits respectively and add the mantissa of the sum of the decimal digits to be the tens of digits of the numerator. Specific to the above example, 2×5+4×6+1=35, where 5 is the decimal digit of the result and 3 is the decimal digit;
the rest of the number is determined by taking the sum of the product of the decimal digits of two numbers and the decimal digits, which is the hundred or thousand digits of the number. Specific to the above example, 4×5+3=23. Then 2 and 3 are thousands and hundredths of the number respectively.
therefore, 42×56=2352. For another example, 82×97, according to the above calculation method, first determine the number of single digits, 2×7=14, then the number of single digits should be 4; Then determine the decimal digit of the numerator, 2×9+8×7+1=75, and the decimal digit of the numerator is 5; Finally, the rest of the number is calculated, 8×9+7=79, so 82×97=7954. Similarly, with this algorithm, it is easy to get the product of all two-digit multiplication.
Quick calculation 1: Quick mental arithmetic-a teaching mode that is really synchronized with the primary school mathematics textbooks
Quick mental arithmetic is the only method to perform simple operations without any physical objects at present, and it does not need to practice abacus, wrench fingers or abacus.
The arrangement and difficulty of the textbook of quick mental arithmetic is a quick calculation that closely follows the elementary school mathematics syllabus and integrates with junior high school algebra, which is simpler than the elementary school textbook. Simplified written calculation and strengthened oral calculation. It is simple, easy to learn and interesting. After a short period of training, primary school students can write answers directly by adding, subtracting, multiplying, dividing and not arranging vertically.
The peculiar effect of quick mental arithmetic
I have learned all the multiplication, division and addition of arbitrary digits above grade three.
In grade two, the multiplication of two digits and the division of one digit.
In grade one, the addition and subtraction of multiple digits.
In kindergarten, large classes learn the addition and subtraction of multiple digits tailored for preschool children, so they have passed the primary school oral calculation in advance. It is helpful for children to learn quick mental arithmetic in kindergarten to go to primary school in the future. Children do their homework without using draft paper, and write answers directly according to their calculations.
Quick mental arithmetic is different from abacus mental arithmetic and hand mental arithmetic. Fast mental arithmetic invented by Niu Hongwei, a teacher in Xi 'an. (Teacher Niu Hongwei obtained the patent certificate issued by the People's Republic of China and China National Intellectual Property Administration. Patent number; ZL28 31174275. It is protected by the patent law of the People's Republic of China. ) mainly through certain rules in the textbook, children are trained in fast operation of addition, subtraction, multiplication and division. "Quick mental arithmetic" helps to improve the orderliness, logicality and sensitivity of children's thinking and behavior, and trains children's eyes, hands and brains to react synchronously and quickly. The calculation method is consistent with mathematics in primary and secondary schools, so it is very popular with parents of young children.
Fast mental arithmetic is a teaching mode that is really synchronized with primary school mathematics textbooks:
1. Learning arithmetic-written arithmetic training. At present, China's education system is exam-oriented education, and the standard for testing students is exam transcripts. Then students' main task is to take exams, answer questions and write them with a pen, and written arithmetic training is the main line of teaching. Consistent with the mathematical calculation method in primary schools, it does not use any physical calculation, and it can be used freely in horizontal and vertical directions, even adding and subtracting. Using a pen to calculate is a golden key to start the smart express.
2: be clear about arithmetic-play with arithmetic. Being able to write questions with a pen not only makes children know arithmetic, but also makes them understand arithmetic. Make children understand the calculation principle and break through the calculation of numbers in spelling. Children complete calculations on the basis of understanding.
3. Practice speed-speed training. It's not enough to calculate problems in writing. Primary schools should have a time limit for oral calculation. It takes time to speak whether they meet the standards, that is, it's not enough to calculate problems. The main thing is to speed up.
4. Enlightening wisdom-intellectual gymnastics, not only learning calculation, but also focusing on cultivating children's mathematical thinking ability, fully stimulating the left and right brain potentials and developing the whole brain. After quick mental arithmetic training, before school