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Ch. 2 - Acute Angles and Right Triangles
Lial - Trigonometry 12th Edition
Lial12th EditionTrigonometryISBN: 9780136552161당신이 사용하는 게 아니라요?교과서 변경
3장, 문제 47

Solve each right triangle. In Exercise 46, give angles to the nearest minute. In Exercises 47 and 48, label the triangle ABC as in Exercises 45 and 46. A = 39.72°, b = 38.97 m

검증된 단계별 안내
1
Identify the given elements of the right triangle: angle \(A = 39.72^\circ\) and side \(b = 38.97\) m. Since this is a right triangle, one angle is \(90^\circ\), and the other two angles sum to \(90^\circ\).
Recall the labeling convention: side \(a\) is opposite angle \(A\), side \(b\) is opposite angle \(B\), and side \(c\) is the hypotenuse opposite the right angle \(C = 90^\circ\).
Use the sine function to find the hypotenuse \(c\) because \(\sin A = \frac{a}{c}\) and side \(b\) is given, so first find angle \(B = 90^\circ - A\) to relate side \(b\) to \(c\) using \(\sin B = \frac{b}{c}\).
Calculate the length of the hypotenuse \(c\) using \(c = \frac{b}{\sin B}\), where \(B = 90^\circ - 39.72^\circ\).
Find side \(a\) using the Pythagorean theorem \(a = \sqrt{c^2 - b^2}\) or use the sine function \(a = c \sin A\). Finally, express all angles to the nearest minute by converting decimal degrees to degrees and minutes.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
5m
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주요 개념

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

Right Triangle Properties

A right triangle has one angle of 90°, and the other two angles sum to 90°. Understanding this helps in determining unknown angles or sides when some parts are given, using the fact that the sum of all angles is 180°.
추천 영상:
5:35
30-60-90 Triangles

Trigonometric Ratios (Sine, Cosine, Tangent)

Trigonometric ratios relate the angles of a right triangle to the lengths of its sides. For example, sine of an angle is opposite side over hypotenuse, cosine is adjacent over hypotenuse, and tangent is opposite over adjacent. These ratios are essential for finding missing sides or angles.
추천 영상:
5:08
Sine, Cosine, & Tangent of 30°, 45°, & 60°

Angle Measurement and Conversion

Angles can be measured in degrees, minutes, and seconds, where 1 degree = 60 minutes. Converting decimal degrees to degrees and minutes is important for precise answers, especially when the problem asks for angles to the nearest minute.
추천 영상:
5:31
Reference Angles on the Unit Circle