Radicals
Definition of a radical
When people talk of a "square root," they're
referring to a radical with a root of 2. This is
mathematically equivalent to a number raised to the power of
1/2. This equivalence is useful to know when using a
calculator to determine a strange root. Suppose for example
you needed to find the fourth root of a number, but your
calculator lacks a "4th root" button or function. If it has
a yx function (which any scientific calculator
should have), you can find the fourth root by raising that
number to the 1/4 power, or x0.25.
It is important to remember that when
solving for an even root (square root, fourth root,
etc.) of any number, there are two valid answers. For
example, most people know that the square root of nine is
three, but negative three is also a valid answer,
since (-3)2 = 9 just as 32 = 9.
Properties of radicals
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