Question 86710
use descartes' Rule of Signs to determine the possible number of positive real zeros of the function  f(x)=-5x^3+x^2-2x+5
--------
# of positive zeroes = # of sign changes or some multiple of 2 less 
# of changes = 2
f(x) has 2 or 0 positive zeroes
-----------------------
f(-x)=5x^3+x^2+2x+5
# of changes = 0
f(x) has 0 negative zeroes
-----------------
Cheers,
Stan H.