A negative power means the quantity is in the denominator of a fraction.
(2) to the -1 power means 1/2
6 to the -3 power means 1/(6 to the 3 power).
13xy to the -8 power means 1 / (13xy to the 8 power)
That's something like 1 / [ (13 to the 8 power) (x to the 8 power) (y to the 8 power) ]
The expression 13 x y − 8 is already simplified and can be evaluated or analyzed further depending on specific tasks. It cannot be factored simply, and if set to zero, reveals a relationship between x and y . You can also substitute specific values for x and y to calculate a numerical result.
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