Differential autorotation type first important limit demonstration instrument

Abstract

The invention relates to a differential autorotation type first important limit demonstration instrument which comprises a bracket, a central tube shaft, an arc lamp, a tangent lamp, a radial rotating lamp, a radial positioning lamp, a tangent lamp and a rocking handle, and is characterized in that a bracket main body is a cuboid front opening box frame, the central tube shaft is arranged in the middle of a rear plate of the bracket box frame; the arc lamp and the radial positioning lamp are respectively arranged at the front part of the central tube shaft in the box frame, the tangent lamp is arranged between an upper frame plate and a lower frame plate of the bracket box frame, the radial rotating lamp and the rocking handle are respectively arranged at two ends of a rotating shaft in the central tube shaft, and the secant lamp is arranged on the radial rotating lamp and the radial positioning lamp. The first important limit and related problems can be visually proved by combining multiple graphs or different curves, the instrument can be widely used as a tool for a long time, and the instrument has the advantages that operation is easy, and all functions can be completed only by rocking the rocking handle. The functions are complete, the structure is compact, the cost is low, the carrying is convenient, and the applicability is high.

Description

Technical field: [0001] The invention relates to the field of teaching display devices, in particular to a differential rotation type first important limit demonstrator. Background technique: [0002] The calculation of limits is the most basic work of advanced mathematics and the most important method to solve calculus. The formula called the first important limit is the core of solving the limit of functions related to trigonometric functions. It has always been the focus and difficulty in teaching. Usually The proof is: on the unit circle with the same included angle of 0 radians and 3 figures contained inside and outside, their shapes and areas are different when the included angle is larger, and the area in the dynamic area is not the same but Finally, they are unified together to obtain the formula result. Teachers often use static sketches and oral descriptions when teaching due to insufficient conditions. There is no dynamic, clear and intuitive change process to pr...

AI Technical Summary

Problems solved by technology

This technology only statically explains the problem of limit points, and cannot intuitively explain the dynamic change relationship of multiple graphics of the first important limit, and its applicability is insufficient

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