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Area is a quantity indicating the degree of a two-dimensional figure or shape or plane layer in a plane. A surface region is a simulation on a two-dimensional surface of a three-dimensional object. Area can be understood as the amount of material with a given thickness, which is necessary to form a shape model.
When the space occupied by an object is a two-dimensional space, the size of the space occupied is called the area of the object, which can be plane or curved. Square meters, square decimeters and square centimeters are recognized units of area and can be expressed as (m? ，dm？ ，cm？ )。
Area is a quantity indicating the degree of a two-dimensional figure or shape or plane layer in a plane. A surface region is a simulation on a two-dimensional surface of a three-dimensional object. Area can be understood as the amount of material with a given thickness, which is necessary to form a model of shape, or the amount of paint required to cover a surface with a single coating.
It is a two-dimensional simulation of curve length (one-dimensional concept) or solid volume (three-dimensional concept). The area of a shape can be measured by comparing a fixed size shape with a square. In the International System of Units (SI), the standard unit area is square meters, the square area is one meter long, and the shape of three square meters will be the same as three such squares.
In mathematics, the unit square is defined as 1, and the area of any other shape or surface is a dimensionless real number. There are several well-known formulas for simple shapes, such as triangle, rectangle and circle.
Using these formulas, you can find the area of any polygon by dividing it into triangles. For shapes with curved boundaries, calculus is usually needed to calculate the area. In fact, the problem of determining the digital area of aircraft is the main driving force for the historical development of calculus.
For solid shapes such as spheres, cones or cylinders, the area of the boundary surface is called the surface area. The surface area formula of simple shapes was calculated by the ancient Greeks, but calculating the surface area of more complex shapes usually requires multivariable calculus.