Skip to main content
Ch. 3 - Radian Measure and The Unit Circle
Lial - Trigonometry 12th Edition
Lial12th EditionTrigonometryISBN: 9780136552161당신이 사용하는 게 아니라요?교과서 변경
4장, 문제 8

CONCEPT PREVIEW Find the area of each sector.

검증된 단계별 안내
1
Identify the given information for the sector: the radius \(r\) of the circle and the central angle \(\theta\) of the sector. The angle should be in degrees or radians.
Recall the formula for the area of a sector: \(\text{Area} = \frac{\theta}{360} \times \pi r^{2}\) if \(\theta\) is in degrees, or \(\text{Area} = \frac{1}{2} r^{2} \theta\) if \(\theta\) is in radians.
If the angle \(\theta\) is given in degrees, use the first formula. If it is in radians, use the second formula. Convert the angle to the appropriate unit if necessary.
Substitute the values of \(r\) and \(\theta\) into the chosen formula to set up the expression for the area of the sector.
Simplify the expression to find the area of the sector (do not calculate the final numeric value unless asked).

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
도움이 되었나요?

주요 개념

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

Definition of a Sector

A sector of a circle is a portion bounded by two radii and the arc between them. It resembles a 'slice' of the circle, and its size depends on the central angle that subtends the arc.
추천 영상:
가이드 코스
04:26
Parameterizing Equations Example 1

Formula for Area of a Sector

The area of a sector is given by (θ/360) × πr² when θ is in degrees, where r is the radius of the circle. This formula calculates the fraction of the circle's area corresponding to the central angle.
추천 영상:
가이드 코스
4:30
Calculating Area of ASA Triangles

Conversion Between Radians and Degrees

Angles can be measured in degrees or radians. Since the sector area formula depends on the angle unit, converting between radians and degrees (1 radian = 180/π degrees) is essential for correct calculations.
추천 영상:
가이드 코스
5:04
Converting between Degrees & Radians