In Exercises 59–62, use a calculator to find the value of the acute angle θ in radians, rounded to three decimal places. cos θ = 0.4112
Ch. 1 - Angles and the Trigonometric Functions

1장, 문제 1.1.75
In Exercises 75–78, find the area of the sector of a circle of radius r formed by a central angle θ. Express area in terms of π. Then round your answer to two decimal places. Radius, r: 10 meters Central Angle, θ: θ = 18°
검증된 단계별 안내1
Recall the formula for the area of a sector of a circle: \(\text{Area} = \frac{\theta}{360^\circ} \times \pi r^2\), where \(\theta\) is the central angle in degrees and \(r\) is the radius of the circle.
Substitute the given values into the formula: \(r = 10\) meters and \(\theta = 18^\circ\), so the area becomes \(\frac{18}{360} \times \pi \times 10^2\).
Simplify the fraction \(\frac{18}{360}\) to its lowest terms to make calculations easier.
Calculate the expression \(\pi \times 10^2\) which represents the area of the full circle, then multiply by the simplified fraction to find the sector area in terms of \(\pi\).
Finally, use the approximate value of \(\pi \approx 3.1416\) to compute the numerical value of the sector area and round your answer to two decimal places.

비슷한 문제에 대한 검증된 영상 답변:
이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
3m도움이 되었나요?
주요 개념
질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.
Area of a Sector
The area of a sector of a circle is the portion of the circle's area enclosed by two radii and the arc between them. It is calculated as (θ/360) × π × r² when θ is in degrees, where r is the radius and θ is the central angle.
추천 영상:
가이드 코스
Calculating Area of SAS Triangles
Central Angle in Degrees
The central angle θ is the angle formed at the center of the circle by two radii. When given in degrees, it must be used directly in the sector area formula as a fraction of 360°, representing the full circle.
추천 영상:
Coterminal Angles
Rounding Numerical Results
After calculating the exact area in terms of π, numerical approximation involves substituting π ≈ 3.1416 and rounding the final answer to the specified decimal places, here two decimals, to provide a practical and understandable result.
추천 영상:
Find the Angle Between Vectors
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