This is really confusing. for .

use descartes’s rule of signs to describe the real zeroes of the function f(x) = 2x^5 - x^4 -2x^3 + 4x^2 + x - 2.

a. the function has two or zero positive real zeroes and either three or one negative real zeroes.
b. the function has two or zero negative real zeroes and either three or one positive real zeroes.
c. the function has one positive real zeroes and either four or two negative real zeroes.
d. the function has one negative real zeroes and either four or two positive real zeroes.