How many sign changes does P(x)=x5+2x4−x3−x2+3x−1P(x) = x^5 + 2x^4 - x^3 - x^2 + 3x - 1P(x)=x5+2x4−x3−x2+3x−1 have? Use Descartes' Rule for positive roots.
444, 222, or 000
333 or 111
222 or 000
555, 333, or 111