Skip to main content
Ch. 1 - Functions
Hass - Thomas' Calculus 15th Edition
Hass15th EditionThomas' CalculusISBN: 9780137616077당신이 사용하는 게 아니라요?교과서 변경
1장, 문제 68

In Exercises 65–68, ABC is a right triangle with the right angle at C. The sides opposite angles A, B, and C are a, b, and c, respectively.


a. Express sin A in terms of a and c.
b. Express sin A in terms of b and c.

검증된 단계별 안내
1
Step 1: Understand the problem setup. We have a right triangle ABC with the right angle at C. The sides opposite angles A, B, and C are labeled as a, b, and c, respectively. In a right triangle, the side opposite the right angle is the hypotenuse, which is c in this case.
Step 2: Recall the definition of the sine function in a right triangle. The sine of an angle is defined as the ratio of the length of the side opposite the angle to the length of the hypotenuse.
Step 3: To express sin A in terms of a and c, use the definition of sine. Since angle A is opposite side a and the hypotenuse is c, we have: sin A=ac
Step 4: To express sin A in terms of b and c, we need to use the Pythagorean identity. In a right triangle, the square of the hypotenuse (c) is equal to the sum of the squares of the other two sides (a and b). Therefore, c2=a2+b2. Solve for a: a=c2-b2
Step 5: Substitute the expression for a from Step 4 into the sine formula from Step 3 to express sin A in terms of b and c: sin A=c2-b2c

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
2m
도움이 되었나요?

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Sine Function

The sine function is a fundamental trigonometric function defined for a right triangle as the ratio of the length of the side opposite an angle to the length of the hypotenuse. For angle A in triangle ABC, sin A = opposite/hypotenuse = a/c, where 'a' is the side opposite angle A and 'c' is the hypotenuse.
추천 영상:
5:53
Graph of Sine and Cosine Function

Right Triangle Properties

In a right triangle, the relationship between the angles and sides is governed by the Pythagorean theorem and trigonometric ratios. The right angle (90 degrees) allows for the use of sine, cosine, and tangent to relate the angles to the lengths of the sides, which is essential for solving problems involving right triangles.
추천 영상:
06:21
Properties of Functions

Trigonometric Ratios

Trigonometric ratios are the ratios of the lengths of sides of a right triangle relative to its angles. These ratios (sine, cosine, tangent) are used to express relationships between the angles and sides, allowing for the calculation of unknown lengths or angles in triangle ABC, particularly in expressing sin A in terms of different sides.
추천 영상:
6:04
Introduction to Trigonometric Functions