MathematicsBeginner

Circumference

C = πd = 2πr

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Core concepts

Formulas

=π = \pi
=2πr = 2\pi r

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dd
=2
cm\text{cm}
3.14×2=6.28 cm\begin{aligned}3.14 \times 2 &= 6.28\ \text{cm}\end{aligned}

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Quantities in the formula
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π\pi
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Glossary

Pi

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