Mathematics knowledge in the second grade of primary school
Knowledge points to know the time:
1, 1 =(60) points.
2. The number upstream of the clock face (12), which divides the clock face into (12) equal grids, and each grid is divided into (5) equal grids, and there are (60) small grids on the clock face.
There are (2) hands on the clock face. The shorter needle is called (hour) needle, and the longer needle is called (minute) needle. When the minute hand walks at 1, it is (1) minutes, when the big hand walks at 1, it is (5 minutes), and when the hour hand walks at 1, it is (1). Minute hand from 12 to 6, go (30 points); The clockwise clock went from 12 to 6, and walked for (6) hours; Clockwise hand made a circle from 12, then returned to 12 and left (12).
4. (30) minutes can also be said to be half an hour, and (15) minutes can also be said to be a quarter of an hour. For example, 8: 30 is 8: 30, and 9: 00 15 is 9: 15.
At 5 o'clock (3 o'clock or 9 o'clock), the hour hand and the minute hand on the clock face are at right angles.
6. Write down the time on the clock face and draw the minute hand: the third question of the textbook is P 10 1, and the sixth question is P 105.
Mathematics wide-angle knowledge points:
1, when arranging combinations, according to a certain order, so as to avoid duplication or omission. Arrangement is related to order, such as the composition of numbers, the collocation of clothes and trousers, breakfast, queuing and so on. Combination has nothing to do with order, such as digital summation, handshake, juice mixing, etc.
2, 3 people, every two people play a game or shake hands and take pictures. * * * to 3 times.
3. Three nonzero numbers can form six tens and two digits with different digits, such as 4, 5 and 7 can form 45, 47, 54, 57, 74 and 75; If one is 0, it can form four two-digit numbers. For example, 0, 4 and 7 can form 40, 47, 70 and 74.
The Knowledge Point of "Understanding Numbers within 10,000" in Grade Two Mathematics
I. Understanding of Numbers within 1000
1, 10, one hundred is one thousand.
2. When reading, read from a height. There are hundreds in a hundred, ten in ten, and a zero in the middle. No matter how many zeros there are in the end, you don't read them.
3. When writing numbers, you should start from the high position, with hundreds of digits, ten digits and ten digits. Any number without a number will be written as zero.
4. Composition of numbers: According to what number is on each number, it consists of several such counting units.
Second, the understanding of the number within 10000
1, 10 One thousand is ten thousand.
2. Numbers within 10,000 are the same as those within 1000.
3. The minimum two digits are 10, and the two digits of are 99; The minimum three digits are 100, and the three digits are 999; The smallest four digits are 1000, and the four digits are 9999; The smallest five digits are 10000, and the five digits of are 99999.
Three, the whole hundred, integer thousand addition and subtraction
Addition and subtraction methods of 1, integer hundred and integer thousand.
(1) Look at the whole hundred and the whole thousand, and then add and subtract.
(2) Add and subtract the number before 0, and then add the same number of zeros as integer hundred and integer thousand at the end of the obtained number.
Step 2 estimate
Think of a number as its approximation and then calculate it.
Knowledge points of second grade mathematics
unit of length
1, the necessity of unifying length units and the role of length units.
2. Know cm: Know the length of cm, and how long it is greater than 1 cm, expressed by the letter CM; Small objects, in centimeters; Measure the length of an object in centimeters with a ruler.
3, know the meter: know the length of the meter, how long it is greater than 1 meter, represented by the letter m, and large objects are usually measured in meters; Measure the length of an object in meters with a ruler; The relationship between centimeter and meter: 1 meter = 100 centimeter.
4. Know the line segment: The characteristics of the line segment: it is straight and its length can be measured; Will use a ruler to measure the length of line segments (only whole centimeters and meters); According to the number of lines in the graph; Draw a line segment: Draw a line segment according to a given length (only the whole centimeter).
5, problem solving: estimate the length of the object, choose the appropriate length unit (limited to centimeters and meters).
Articles related to the knowledge points of the second grade mathematics encyclopedia;
★ Arrangement of conceptual knowledge points in the first volume of second grade mathematics
★ Important knowledge points in the first volume of second grade mathematics
★ Organize the knowledge points of second-grade mathematics.
★ Arrangement of Mathematics Knowledge Points in Grade Two of Primary School
★ Second grade mathematics knowledge points
★ Summary of key knowledge points in second grade mathematics
★ Sum up the knowledge points in the first volume of the second grade mathematics.
★ Summarize and sort out the knowledge points of second grade mathematics.
★ People's Education Edition second-grade mathematics knowledge points
★ Second grade version of mathematics knowledge points