Your identity says ...
... sum of cubes = (sum)³ -3(product)(sum)
... = 4³ -3·1·4
... = 64 -12 = 52
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The two numbers are 2±√3, and the sum of their cubes is indeed 52.
Answer:
This answer is a function because there are no repeating x values. It is okay if there are repeating y values, the x values are the problem. This one has no repeats though so it is a function!
Step-by-step explanation: