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Ch. 1 - Angles and the Trigonometric Functions
Blitzer - Trigonometry 3rd Edition
Blitzer3rd EditionTrigonometryISBN: 9780137316601당신이 사용하는 게 아니라요?교과서 변경
1장, 문제 53

In Exercises 49–54, find the measure of the side of the right triangle whose length is designated by a lowercase letter. Round answers to the nearest whole number.
Right triangle QRP with angle 39° and side QR measuring 51 m.

검증된 단계별 안내
1
Identify the sides of the right triangle relative to the given angle of 39°. Here, side QR (51 m) is opposite angle P, and side RP is adjacent to angle P.
Determine which side length you need to find. For example, if you want to find side QP (the hypotenuse), use the sine or cosine function based on the given angle and known side.
Set up the trigonometric ratio using the angle and known side. For example, if finding the hypotenuse QP, use the cosine function: \(\cos(39^\circ) = \frac{\text{adjacent}}{\text{hypotenuse}} = \frac{51}{QP}\).
Rearrange the equation to solve for the unknown side. For the hypotenuse, multiply both sides by QP and then divide both sides by \(\cos(39^\circ)\) to isolate QP: \(QP = \frac{51}{\cos(39^\circ)}\).
Calculate the value using a calculator (make sure it is in degree mode), then round the answer to the nearest whole number as required.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
2m
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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 degrees, and the other two angles sum to 90 degrees. The sides are related through trigonometric ratios, and the side opposite the right angle is the hypotenuse, the longest side.
추천 영상:
5:35
30-60-90 Triangles

Trigonometric Ratios (Sine, Cosine, Tangent)

Sine, cosine, and tangent relate the angles of a right triangle to the ratios of its sides. For an angle θ, sine = opposite/hypotenuse, cosine = adjacent/hypotenuse, and tangent = opposite/adjacent. These ratios help find unknown side lengths.
추천 영상:
5:08
Sine, Cosine, & Tangent of 30°, 45°, & 60°

Using Given Angle and Side to Find Unknown Sides

Given one angle (other than 90°) and one side length, you can use trigonometric ratios to find the lengths of the other sides. Identify which side corresponds to opposite, adjacent, or hypotenuse relative to the given angle to apply the correct ratio.
추천 영상:
4:18
Finding Missing Side Lengths