Knowledge points of the sixth grade mathematics book I "Position and direction (II)"
1. According to the direction and distance, the position of the object on the plane can be determined.
2. The method of marking the position of the object on the plan:
First use a protractor to determine the direction, then use a ruler to determine the distance on the map according to the selected unit length, and finally find out the specific position of the object and mark it with the name.
3. When describing the road map, we should first determine each reference point according to the walking route, and then use each reference point to establish a direction marker to describe the direction and distance of the next target, that is, each step should be clear about where to go and how far to go.
4. Method of drawing road map:
(1) Determine the direction mark and unit length.
(2) Determine the position of the starting point.
(3) According to the description, start from the starting point, find the direction and distance and draw them one by one. Except for the first paragraph (with the starting point as the reference point), the end points of the previous paragraph should be the reference points of each other.
(4) Draw a "ten" direction mark with who as the reference point and who as the center, and then judge the direction and distance of the next position.
Knowledge points of "fractional multiplication" in the first volume of mathematics in the sixth grade of primary school
Importance of (1) fractional multiplication:
1, the fractional multiplication of integers has the same meaning as integer multiplication, and it is a simple operation to find the sum of several identical addends.
"Fraction multiplied by integer" means that the second factor must be an integer, not a fraction.
2. Multiplying a number by a fraction means finding the fraction of a number.
"A number multiplied by a fraction" means that the second factor must be a fraction, not an integer. The first factor is anything. )
(2) Calculation rules of fractional multiplication:
1, the calculation method of the fraction multiplied by the integer: the numerator is the product of the numerator multiplied by the integer, and the denominator remains unchanged. What can be reduced is reduced first, and then calculated.
(1) If you can make an appointment, you can make an appointment first and then calculate. (Integer and denominator divisor)
(2) The divisor is to subtract the common factor from the integer and the denominator below. (Integer cannot be multiplied by denominator, and the calculation result must be the simplest fraction).
2. The calculation method of fractional multiplication is: use the product of molecular multiplication as numerator, and use the product of denominator multiplication as denominator. (numerator times numerator, denominator times denominator)
(1) If the fractional multiplication formula contains a band fraction, the band fraction should be converted into a false fraction before calculation.
(2) The method of fractional simplification is that the numerator and denominator are divided by their common factors at the same time.
(3) In the process of multiplication, the divisor is to cross out two divisible numbers in the numerator and denominator, and then write the divisor above and below respectively. (After reduction, the numerator and denominator can no longer contain common factors, so the calculated result is the simplest score).
(4) The basic nature of the fraction: the numerator and denominator are multiplied or divided by the same number (except 0) at the same time, and the size of the fraction remains unchanged.
(3) the relationship between products and elements:
A number (except 0) is multiplied by a number greater than 1, and the product is greater than this number. A×b=c, when b >; In 1, c> answer.
A number (except 0) is multiplied by a number less than 1, and the product is less than this number. A×b=c, when b < 1, c
A number (except 0) is multiplied by a number equal to 1, and the product is equal to this number. A×b=c, and when b= 1, c = a.
When comparing the sizes of factors and products, we should pay attention to the special situation when the factor is 0.
Knowledge points of sixth grade mathematics in People's Education Edition
proportion
1. Understand the meaning and basic properties of proportion, and know how to solve the proportion.
2. Understand the meaning of positive proportion and inverse proportion, find out the examples of positive proportion and inverse proportion in life, and use proportional knowledge to solve simple practical problems.
3. Knowing the image of the proportional relationship, you can draw an image on the grid paper with coordinate system according to the given data of the proportional relationship, and you will find out or estimate the value of the other quantity in the image according to one of them.
If you know the scale, you will find the scale of the plan and the distance or actual distance on the map according to the scale.
5. Understand the phenomenon of zooming in and zooming out, and you can zoom in or zoom out simple graphics in a certain proportion in the form of grid paper to realize the similarity of graphics.
6. Infiltrate the thought of function, and let students be inspired by dialectical materialism.
7. Meaning of proportion: Two expressions with equal proportion are called proportion. For example: 2: 1 = 6:
8. The four numbers that make up a proportion are called proportional items. The two items at both ends are called external items, and the two items in the middle are called internal items.
9. Nature of proportion: In proportion, the product of two external terms is equal to the product of two internal terms. This is the basic nature of the so-called proportion. For example, from 3: 2 = 6: 4, we can know that 3× 4 = 2× 6; Or multiply by x x 1. 5=y× 1 .2 x: y = 1.2: 1.5。
10. solution ratio: According to the basic nature of the proportion, if any three items in the proportion are known, another unknown item can be found in this numerical proportion.
Finding the unknown term in the proportion is called the solution ratio.
For example: 3: x = 4: 8, the inner term is multiplied by the inner term, and the outer term is multiplied by the outer term, so: 4x = 3x8, and x=6 is obtained.
Sixth grade mathematics knowledge points induction related articles;
★ Sort out and summarize the knowledge points of the first volume of mathematics in the sixth grade.
★ Organize the knowledge points of the sixth grade math review (full version)
★ A Complete Collection of Mathematics Learning Methods and Skills in the Sixth Grade of Primary School
★ Summary of Mathematics Knowledge Points in the Sixth Grade of Primary School
★ Review the knowledge points in the first volume of sixth grade mathematics.
★ Summary of knowledge points in the first volume of sixth grade mathematics
★ Summary of knowledge points in sixth grade mathematics circle
★ Summary of sixth grade mathematics knowledge
★ Integration of review materials of mathematics knowledge points in grades one to six.