"Values ​​of trigonometric functions for angles of 30°, 45°, and 60°" PPT courseware on the relationship between the sides and angles of a right triangle

Description

"Values ​​of trigonometric functions for angles of 30°, 45°, and 60°" PPT courseware on the relationship between the sides and angles of a right triangle

Learning objectives for this lesson

1. Use the definition of trigonometric functions to find the trigonometric function values ​​of special angles such as 30°, 45°, and 60°.

2. Ability to calculate trigonometric function values ​​for angles of 30°, 45°, and 60°.

3. Be able to explain the size of the corresponding acute angle based on the trigonometric function values ​​of 30°, 45°, and 60°.

Knowledge review

As shown in the figure, ∠ C=900, find sinA, cosA, tanA, sinB, cosB, tanB

Think about it:

If you know the value of a certain trigonometric function of an acute angle, can you find this acute angle? For example, tanA=1, what is the degree of acute angle A?

Example questions and demonstrations

[Example 1]Calculation:

(1)sin30°+cos45°;

(2)sin260°+cos260°.

knowledge application

1. There is an escalator in a shopping mall with an inclination angle of 30° and a height of 7m. What is the length of the escalator?

2. As shown in the picture, Xiaoli, who is 1.5m tall, uses a triangle ruler with two acute angles of 300 and 600 to measure the height of a tree. It is known that the distance between her and the tree is 5m, then how tall is the tree approximately? ?

3. A child swings on a swing. The length of the swing chain is 2.5m. When the swing swings to both sides, the swing angle is exactly 60°, and the swing angles on both sides are the same. Find the angle when it swings to the highest position and when it swings to the lowest position. height difference

Expand your thinking

A certain city plans to plant a certain kind of turf on a triangular open space as shown in the picture in the "old city reconstruction" to beautify the environment. Knowing that this kind of turf costs a yuan per square meter, how much is the minimum cost to purchase this kind of turf.

Keywords: teaching courseware on the relationship between sides and angles of a right triangle, teaching courseware on trigonometric function values ​​of angles 30°, 45° and 60°, Beijing Normal University edition ninth grade mathematics volume 2 PPT courseware, ninth grade mathematics slide courseware download, sides of a right triangle Angle relationship PPT courseware download, trigonometric function values ​​of 30°45°60° angle PPT courseware download, .ppt format

For more information about the PPT courseware "The relationship between the sides and angles of a right triangle and the value of the trigonometric function of the angle 30°45°60°", please click the "The relationship between the sides and angles of a right triangle ppt The value of the trigonometric function of the angle 30°45°60°" ppt tag.

"Values ​​of trigonometric functions for angles of 30°, 45°, and 60°" Relationship between sides and angles of right triangles PPT courseware 4:

"Values ​​of trigonometric functions of angles 30, 45, and 60" PPT courseware 4 on the relationship between the sides and angles of a right triangle. The problem is as shown in the figure. In Rt△ABC, C=90AC=aA=30. Find BC. Analysis 1. From C=90A=30 we think What? 2. Assume BC=x, then what is AB equal to? 3. Next, as...

"Values ​​of trigonometric functions for angles of 30°, 45°, and 60°" The relationship between the sides and angles of a right triangle PPT courseware 3:

"Trigonometric Function Values ​​of 30, 45, and 60 Angle" PPT courseware on the relationship between the sides and angles of a right triangle 3 Thinking How many different acute angles are there in the two set square rulers? Find the sine, cosine and tangent values ​​of these acute angles respectively. Example 1: Find the values ​​of the following formulas: (1) 2sin26..

"Values ​​of trigonometric functions for angles of 30°, 45°, and 60°" Relationship between sides and angles of a right triangle PPT courseware 2:

"Trigonometric function values ​​of angles 30, 45 and 60" The relationship between the sides and angles of a right triangle PPT courseware 2 Review and consolidation As shown in the figure, in Rt△ABC, C=90. (1) The relationship between a, b, and c is ______, A+B=______. (2) sinA=______, cosA=..

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Update Time: 2024-10-04

This template belongs to Mathematics courseware Beijing Normal University Ninth Grade Mathematics Volume 2 industry PPT template

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