A, perimeter formula:
1, the perimeter of the rectangle = (length+width) ×2.
2. The circumference of a square = side length ×4.
3. (Key) The circumference of a circle = π× diameter = 2×π× radius.
Second, the area formula:
1, rectangular area = length × width.
2. Area of a square = side length × side length.
3. Area of triangle = base × height ÷2.
4. The area of parallelogram = base × height.
5. Trapezoidal area = (upper bottom) × height ÷2.
6. Area of (key) circle = π× radius 2.
7. (Key) lateral area of the cylinder: lateral area of the cylinder is equal to the perimeter of the bottom multiplied by the height.
8. (Key) Cylinder surface area: Cylinder surface area = bottom area+side area.
Math learning skills:
1, take notes:
This method is actually very common and simple, but it is difficult for many students to do it. Taking notes has many advantages. First, you can record the essence of the teacher for review. Second, it can train students' writing ability. Thirdly, it can help students develop their learning ability in listening and writing, which is very effective in improving learning efficiency.
2. Wrong title:
Many children are sloppy, but some sloppy are actually caused by students' unclear understanding of knowledge points. Such a topic must be recorded. There are also traps deliberately designed by questioners, which can also be recorded and reviewed regularly. After a long time, many carelessness will naturally be avoided.
3, study group:
Sharing good test questions, methods, skills and experiences with group members on a regular basis can not only increase the affection between classmates, but also learn new things in the process of making friends, improve learning efficiency, cultivate cooperation spirit and enhance coordination ability.
4, topic classification:
I like the wrong problem book and record the problems I have done. Classification refers to dividing the problems I have done into several categories, one of which is extremely simple and can be read by myself.
One kind is difficult, which requires thinking to find a breakthrough, and the other kind is difficult, which requires comprehensive application of a lot of knowledge and truth to solve. The latter two should be the focus of the record. In the process of classifying the test questions, students naturally enhance their further understanding of the test questions.