Radian

/ˈreɪdiən/

Definition 1 of 1

Pro Tip 1/3

Imagine wrapping a circle's radius along its edge to see the radian angle it creates.

If you visualize a pizza slice, one radian would be a slice where the crust's arc is equal to the radius of the pizza.

Pro Tip 2/3

Understand the conversion between radians and degrees, since 180 degrees is equal to π radians.

To find an angle in radians, divide the degrees by 180 and multiply by π.

Pro Tip 3/3

Know that radians are used in mathematical expressions involving trigonometry and calculus.

The formula for the area of a sector is (1/2)*r^2*θ, where θ is the angle in radians.

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