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A LITTLE SOMETHING WORTH KNOWING

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Math & LogicOne small ahaGeometry

Circumference of a circle

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Math & LogicOne small aha
Your new aha2πr

Lengths use linear units, areas use square units, and volumes use cubic units. Source: Geometry ↗

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More from Geometry Essentials

A few more worth knowing.

  1. 06Area of a circleRECALL
    πr²

    r is the radius

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  2. 07Right triangle with hypotenuse c · Pythagorean equationRECALL
    a² + b² = c²

    Applies to right triangles

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  3. 08Shape with five sidesRECALL
    Pentagon

    Interior angles sum to 540°

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