Root of a negative number
To calculate the root of a negative number, it must be reduced to an arithmetic root, with
Example 1
Negative numbers can be converted with the imaginary unit. Then you no longer have a minus sign. With a division you get
where a and b are positive numbers.
Example 2
The calculation
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is wrong, although the outcome here happens to be correct. The property
applies only to arithmetic roots. Algebraic roots must first be reduced to arithmetic roots.
Example 3
The division
gives a positive number, but you probably wouldn't have expected anything else.