Math story of the first grade in primary school
When Gauss was in elementary school, once after the teacher taught addition, because the teacher wanted to have a rest, he came up with a topic for students to calculate. The topic is:1+2+3+...+97+98+99+100 =? The teacher is thinking, now the children must start class! I used this as an excuse to go out, but Gauss stopped me! ! It turns out that Gauss has worked it out. Little friend, do you know how he did it? Gauss told us how he worked it out: add 1 to 100, and add 100 to 1, adding two lines. That is to say:1+2+3+4+……+96+97+98+99+100+99+98+97+96+…+4+3+2+65438. 5438+001+10/+1kloc-0/there are 100 and1kloc-0/,but the formula is repeated twice.
The second part of the math story of the first grade in primary school
In the mysterious kingdom of mathematics, two "secondary numbers", namely "0" of the fat man and "1" of the thin man, often argue endlessly about who is important. Look! Today, these two little enemies meet in a narrow way, and they have launched another war of words. The thin man 1 spoke first: "Hum! Fat' 0', what's so great about you? Just like 100, what's the use of you two being fat without my thin'1'?"
Fat man "0" is not convinced: "Don't be overbearing in front of me. Think about it. Without me, where can you find other figures to make up 100? "
"hey!" "1" is not to be outdone. "No matter how arrogant you are, you are insignificant. Look! 1+0' is not equal to myself. What's your use? "
"Let's go! The result of'1× 0' is not me, and your'1'is also useless! " "0" is tit for tat.
"You ..." "1"paused and improvised. "Anyway, your' 0' doesn't mean anything!"
"This is your lack of knowledge." "0" said unhurriedly, "You see, in daily life, the temperature is 0 degrees. Is there no temperature? For another example, without my starting point on the ruler, how can there be'1'?"
"No matter how you compare, you can only do the middle number or mantissa, such as 1037, 1307, and you can never lead." 1 "said confidently. "0" a listen to, more confidently said: "this may be unknown, such as 0. 1, what can you do without my' 0'? "
Seeing the fat man "0" and the thin man "1" all blushed, and no one would let anyone, and other people watching were very anxious. At this time, "9" had a brainwave and made a gesture of pause: "You two stop arguing. Look at you, which size is bigger than me? " "This ..." The fat man "0" and the thin man "1" were speechless. At this time, "9" said calmly: "1" and "0". In fact, as long as you stand together, aren't you older than me? "1" and "0" looked at each other, and it took a long time to scratch their heads and laugh. " That's right! The power of unity is the most important! ""No.9 "said earnestly.
The third part of the math story of the first grade in primary school
The symbols "+"and "-"were first used by Germans 500 years ago. It is said that at that time, after the wine merchants sold out, they marked the wine in the barrel with horizontal lines, and when the wine in the barrel increased again, they crossed out the original horizontal lines with vertical lines. So "-"means decrease and "+"means increase. 1489, German mathematician Weidemann first used "+"and "-"to express surplus and deficiency in his works. Later, after the propaganda and advocacy of the French mathematician Veda, it began to spread, and it was not until 1630 that it was recognized by everyone. More than 300 years ago, the British mathematician Audley first used the multiplication symbol "×". He thought multiplication was a special form of addition, so he turned the "x" invented by his predecessors by 45 degrees, and the multiplication symbol "x" came out. "X" indicates both the relationship between multiplication and addition and the method of multiplication. Division symbol "∫"-At first, this symbol was very popular in continental Europe as a minus sign. At first, people used ":"to indicate division or ratio, while others used the fractional line "-"to indicate ratio. Later, some people combined the two into "∫", and the Swiss mathematician Laha officially used "∫" as a division symbol in his works.
The fourth part of the math story of the first grade in primary school
In the activity class, Mr. Black Bear smiled and said to everyone, "Shall we play a game?" "good!" The little animals answered in unison. "Please prepare two small notes for each of you." Teacher Black Bear cleared his throat and said. These little animals don't know what game Mr. Black Bear wants them to play. One by one, their excited eyes lit up, and soon all the little notes were ready.
Teacher Black Bear looked around the class and said, "Please write an odd number and an even number on two small pieces of paper, and then take one in each hand. Don't show it to me or your classmates. "
Small animals just learned odd and even numbers not long ago, and in a short time, everyone met the requirements put forward by Mr. Black Bear. "Listen," Mr. Black Bear said clearly, word by word, "please multiply the number in your right hand by 2, the number in your left hand by 3, and then add up the products. Don't work out the sound. "
When all the animals are counted, Mr. Black Bear tells the odd-numbered animals to line up. If the number of people is even, line up. The little animals stood still, looking at Mr. Black Bear with interest, guessing what he wanted them to do next.
"All right!" Teacher Black Bear pointed to the odd-numbered row of small animals and said, "You have an odd number in your left hand."
It pointed to another row of small animals and said, "You have an even number in your left hand."
Two rows of small animals spread their palms, but yes, Mr. Black Bear is absolutely right.
Small animals were so surprised that they couldn't help asking, "Teacher, how do you know?"
The black bear teacher then analyzed: "
Odd number × 2 = even number
Odd number × 3 = odd number
Even number × 2 = even number
Even number × 3 = even number
Even number+even number = even number
Even+odd = odd
When the left hand is odd, odd ×3 is odd, odd+even (right hand is even ×2), and the result is odd. And if the right hand is odd, odd ×2 becomes even, even+even (the left hand is even ×3), and the result is even.
This is the reason why the final result is the same as the odd-even number of the left hand, and it is also the basis of my guess. "
The little animals suddenly realized.
The fifth part of the math story of the first grade in primary school
1, Su Dongpo, a great poet in the Song Dynasty, went to Beijing with several younger brothers to catch the exam when he was young. It was too late when they arrived at the hospital. The examiner said, "I'll make a couplet. If you are right, I will let you into the examination room. " The examiner's first contact is: a leaf, sitting alone with two or three students, using four oars and five sails, passing through six beaches and seven bays, experiencing eight bumps and nine winnows, alas, ten minutes late. Su Dongpo's bottom line is: ten years of cold window, entering the 98 th hospital, abandoning worldly desires, studying hard the Five Classics and Four Books, and taking exams three times and twice. Today, he must win
The examiner and Su Dongpo both embedded ten numbers from one to ten in the couplets, which vividly described the hardships and hardships of the scholars.
2. Wrong decimal point
Learning mathematics is not only to solve problems correctly, but also to make no mistakes in the specific problem-solving process, which is often a thousand miles away.
An old woman living on a pension in Chicago, USA, went home after minor surgery in the hospital. Two weeks later, she received a bill from the hospital, amounting to $63,440. When she saw such a huge number, she couldn't help being surprised. She had a heart attack and fell to the ground dead. Later, someone checked with the hospital, and it turned out that the computer had misplaced the decimal point, but actually only needed to pay 63. 44 dollars.
A wrong decimal point actually killed a person. As Newton said, "In mathematics, the smallest error can't be ignored.
When did 3.2 1 century begin?
Century is the unit for calculating age, and a hundred years is a century.
The start year and end year of the first century are 1 and 100 respectively. The common mistake is that some people regard the starting year as the year zero, which obviously does not conform to logic and our habits, because in general, the calculation of ordinal numbers starts from "1" instead of "0". It is this misunderstanding that led to the misunderstanding that the year at the end of the century was 99 AD, which is why 1999 was wrongly considered as the year at the end of the twentieth century and the year 2000 was the year at the beginning of the twenty-first century. Because the AD count is ordinal, it should start with "1", and the first year of 2 1 century is 200 1.