When we use the radical sign √ it means square root. The
square root is actually a fractional index and is equivalent to
raising a number to the power of ½.
Example
So for example 151/2 = √15 = 3.873
You can also have cubed roots, fourth roots and so on.
There are a few key rules to working with roots. First if a and b
are both greater or equal to 0 than:
√ a x b = √a x √b
However this only applies when multiplying, if we are adding
√ a + b ≠ √a + √b
Another common example you will see is √ a2
In this case the answer is a. to solve this you would start
with a and square it, than find the square root, and when you are
done you will see that you are back to a again. This is important
because often times in algebra we need to undo a square when solving
an equation, so we will find the square root of both sides. |
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