Question

According to Descartes' rule of signs, how many possible positive real roots could the following polynomial function have? f(x)=3x^4-5x^3+5x^2+5x+2

Answer 1

A. Three
B. Three or one
C. One
D. Two or zero

Answer 2

\[ f(x)=3x^4\overbrace{-}^{\text{one change in sign}}5x^3\overbrace{+}^{\text{two change in sign}} 5x^2+5x+2 \]

Answer 3

so is it two or zero ?

Answer 4

yes

Answer 5

thank you :)