An obtuse angle is an angle greater than 90 degrees but less than 180 degrees. This definition is intuitive, because we can directly judge whether an angle is obtuse by comparing the size of the angle. In geometry, obtuse angles are usually represented by solid lines to distinguish them from acute angles and right angles.
Second, obtuse angles are also common in daily life. For example, in architectural design, obtuse angles are widely used to construct beautiful curves and streamlined shapes. In nature, obtuse angles also exist in many creatures, such as peacock's tail and the shape of leaves. These shapes and structures can exist because they conform to natural laws and mathematical principles.
Third, the obtuse angle is not only used in daily life, but also of great significance in the fields of mathematics and science. In trigonometric function, the tangent of obtuse angle is negative and the tangent of acute angle is positive. In addition, obtuse angles can also be calculated by inverse trigonometric functions, such as sine function and cosine function. These calculation methods are very useful in solving practical problems such as physics, engineering and economy.
4. An obtuse angle refers to an angle greater than 90 degrees but less than 180 degrees. Although this concept is simple, it is widely used in mathematics, geometry, physics and engineering. Through the understanding and research of obtuse angle, we can better understand the basic concepts and principles of these fields. At the same time, obtuse angle also plays an important role in daily life, which provides us with many beautiful visual effects and practical design ideas.
Learning geometry method
1. Mastering basic concepts: To learn geometry, we must first master basic concepts, such as points, lines, surfaces, angles, triangles, quadrangles, etc. These concepts are the basis of learning geometry and must be mastered skillfully.
2, do more exercises: through a large number of exercises, you can deepen your understanding and memory of geometry knowledge. Doing more exercises can also cultivate problem-solving ideas and skills and improve problem-solving ability.
3. Pay attention to proof questions: proof questions are an important part of geometry learning and need to be practiced. Proving questions can cultivate logical thinking and reasoning ability, which is very helpful to improve the level of geometry.