Say you're given y = x^4 - 4x^2 has the minimim at (2^.5,-4) and (-2^.5,-4)?

Question

are those minimum called local minimum or absolute minimum? or both?

Answer 1

yeah, they are the absolute (or global) minima. These are the 2 lowest points of that (even) function.

Answer 2

Those are absolute minima, because both ends of an x^4 function go in the same direction. There are 0 points lower than those points.

Answer 3

absolute minimum