 Roots and Radicals
 A radical expression is .
 is the radical sign,
a is the radicand, and
m is the index.
 means the square root of a.
 The principal (or positive) square root of the number a is written and is equal to the positive number whose square equals a.
 For this class, "square root" means principal square root.
 means the cube root of a.
 means the m^{th} root of a.
 if b^{m} = a.
 Even Indexes
 The m^{th} root of a,
,
where m is an even index and a is a
positive real number, is that positive
real number b such that b^{m} = a.
 Example: = 3 since 3^{4} = 81.
 Odd Indexes
 The m^{th} root of a,
,
where m is an odd index and a is
any
real number, is that real number b such that b^{m} = a.
 Example: = 4 since 4^{3} = 64.
 Example: = 4 since (4)^{3} = 64.
 Square Roots of Something Squared
 Consider any real number squared. It's square root is the absolute value of that real number.
 Example: = a
 Example: = 6 = 6
 Example: = x  2
