1, proving triangle congruence:
In an isosceles triangle, the bisector of the vertex, the median line on the bottom and the height on the bottom coincide with each other, that is, the three lines are one. Using this property, we can prove the congruence of triangles.
2, determine the triangle center:
When a triangle has three midlines, the intersection of these three midlines is called the center of gravity of the triangle. The center of gravity divides each midline into two sections: 2: 1. So the point where the three lines meet is the center of gravity of the triangle.
3, determine the triangle height line:
In an isosceles triangle, the height of the base is three lines connected into a line. Therefore, the height line of the triangle can be determined according to the unity of the three lines.
Scope of application of three-in-one
1, mathematics field:
In isosceles triangle, we can use the property of three lines in one to prove the congruence of the triangle, or determine the center and high line of the triangle. In addition, other geometric problems can be solved, such as parallelogram, square, circle and so on. Through the unity of three lines, we can solve the angle, prove the similarity of triangles and discover the special properties of quadrilateral.
2, the field of physics:
For example, in electricity, the unity of three lines can be used to calculate physical quantities such as charge distribution and electric field intensity. In mechanics, the unity of three lines can be used to study the motion trajectory and stress of objects.
3. In the field of engineering and economy:
For example, in engineering, the three-in-one property can be used to optimize the design and improve the efficiency. In economics, the trinity can be used to study macro issues such as economic cycle and monetary policy.
4, the field of biology:
The concept of trinity can be used to describe biological phenomena such as cell structure and DNA double helix structure, and help people understand the basic structure and function of organisms.
5. Geographical area:
The concept of trinity can be used to describe the relationship between the earth's rotation axis, the common rotation axis and the polar axis, and then to study the geographical characteristics and climate change of the earth.