Reciprocal In Algebra
Turn it upside down!
Reciprocal of a Number
To get the reciprocal of a number, just divide 1 by the number. |
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Examples:
| Number |
Reciprocal |
As a Decimal |
| 2 |
1/2 |
= 0.5 |
| 8 |
1/8 |
= 0.125 |
| 1,000 |
1/1,000 |
= 0.001 |
Reciprocal of a Variable
If you are given a variable "x", its reciprocal is "1/x".
Likewise, if you are given something more complicated like "x/y" then the reciprocal is just "y/x" (ie, turn it upside down).
Example: What is the Reciprocal of x/(x-1) ?
Answer: take x/(x-1) and flip it upside down: (x-1)/x
Flipping a Flip
If you take the reciprocal of a reciprocal you end up back where you started!

Example:
The reciprocal of ax/y is y/ax
The reciprocal of y/ax is ax/y (back again)
Example: What is:
Answer: w
Notation
The reciprocal of "x" is shown as:
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