Online Math Dictionary: R

Easy to understand math definitions for K-Algebra mathematics
Just scroll down or click on the word you want and I'll scroll down for you!

radian radical radicand
radius of a circle ratio rational number
the denominator
ray reciprocal
of a number
rectangle rectangular
coordinate system
regular polygon
relation relatively prime remainder
repeating decimal rhombus right angle
right triangle root of  a polynomial  


radian is a special unit of measure (like degrees) that measures things that are circular  -- like angles that sweep  around!  You start using radians in trigonometry.
To find out more info about radians, check out my Trigonometry of Circlespage. 
2pi radians = 360 degrees

The measure of an angle...  30 degrees equals  pi/6 radians

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A radical is a root (like a square root) of a number.  A radical is made up ofradical sign and something inside called the radicand.

radical:  The square root of x
Example:   The square root of 4 is 2
To learn more about radicals, check out my Radicals Review lesson.

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The radicand is the thing inside the radical sign.

radicand:  The square root of x