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Excel in math and science
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Properties of Circles
What is pi? If the area of a circle is 49π, what is its circumference? If a circle is inscribed in a square, what is the ratio of the areas of the circle and the square?
Excel in math and science
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Concept Quizzes
Excel in math and science
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by Brilliant Staff
A circular sector with a radius of 10 has an area of 200. What is the central angle (in radians)?
Excel in math and science
Master concepts by solving fun, challenging problems.
It's hard to learn from lectures and videos
Learn more effectively through short, conceptual quizzes.
Our wiki is made for math and science
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examples, and problems from the community.
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That seems reasonable.
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by Brilliant Staff
Excel in math and science
Master concepts by solving fun, challenging problems.
It's hard to learn from lectures and videos
Learn more effectively through short, conceptual quizzes.
Our wiki is made for math and science
Master advanced concepts through explanations,
examples, and problems from the community.
Used and loved by 4 million people
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including olympiad champions, researchers, and professionals.
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by Brilliant Staff
\(\Gamma\) is a circle with radius \(14\) and center \(O\). \(A\) and \(B\) are points on \(\Gamma\) such that the arc length \(\widehat{AB} = 14\). What is the area of sector \(AOB\)?
Excel in math and science
Master concepts by solving fun, challenging problems.
It's hard to learn from lectures and videos
Learn more effectively through short, conceptual quizzes.
Our wiki is made for math and science
Master advanced concepts through explanations,
examples, and problems from the community.
Used and loved by 4 million people
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including olympiad champions, researchers, and professionals.
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by Brilliant Staff
A circular sector with central angle 5 radians has an area of 250. What is its radius?
Excel in math and science
Master concepts by solving fun, challenging problems.
It's hard to learn from lectures and videos
Learn more effectively through short, conceptual quizzes.
Our wiki is made for math and science
Master advanced concepts through explanations,
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Used and loved by 4 million people
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by Brilliant Staff