A solution to calculation of odd roots of negative numbers with Calc

when we try to calculate the cube root of -27 (using the formula = POWER
(A1, 1/3) -3 Calc should give us but gives us the message # VALUE!
I solved the problem by modifying the formula as follows:
=-POWER (-A1, 1/3) and this modification Calc can give us the correct
answer.
Well I think to include this modification in Cal would take a decision
block, suppose that the entries are "numbers, index". The terms of the
decision would be:
if (num <0 & 1/index% 2 = 1)
The first one test if num is a negative number, the second one trys if
index is an odd number, yet if an integer. If true both conditions would be
used if the proposed amendment and was not used the normal function.
If this helps please let me know. I hope not look like a fool. If Cal can
do the calculation differently let me know as it does, thanks for
everything.