Area of rectangle = length × width. Area of a square = side length × side length. Area of triangle = base × height ÷2. Area of parallelogram = base × height. Trapezoidal area = (upper bottom+lower bottom) × height ÷2. Area of circle = π× radius× radius.
Lateral area of cylinder = perimeter of bottom circle × height. Surface area of cylinder = upper and lower bottom area+side area. The surface area of a cuboid = (length× width+length× height+width× height) ×2.
First, expand the information.
The size of the plane figure occupied by objects is called their area. Area is the size of a plane figure, square meters, square decimeters and square centimeters, which is a recognized unit of area and can be expressed as (m? ，dm？ ，cm？ )。
Square meters are metric units of area. It is defined as the area of a square with a side length of 1 m. In life, square meters are usually referred to as "square meters" or "squares" for short. Hongkong and Taiwan Province are called "square meters".
Second, how to learn mathematics well
1. Activity preview
Preview is a general understanding of the relevant knowledge of the course to be studied, which is convenient for you to easily keep up with the teacher's teaching chapters in class. Doing so not only makes passive lectures become active lectures, but also strengthens the effect of lectures and improves learning efficiency. Have a general understanding of the knowledge learned in the next lesson, such as texts, laws, formulas and so on.
Positive thinking
Most students just listen mechanically in the process of listening to the class and can't think on their own initiative. In this way, when facing the questions in the exam, they will have no way to start and don't know how to apply what they have learned to answer them.
The main reason is that I don't think in class. In addition to following the teacher's thinking, we should also think more about why we should define it like this, and what are the benefits of this thinking. Taking the initiative to think like this can not only make us more serious in class, but also stimulate our interest in mathematics knowledge.
3. Be good at summing up laws
Mathematics is a discipline that can grasp the law through thinking, simplify the complex and solve mathematical problems with rules to follow.