Question

Determine the number positive real zeros of the polynomial below. (Type answer in as a whole number)f(x)=x^5+3x^2-4x+2

Answer 1

The number of positive real zeros is 2 or 0

Explanation:

Given

`f(x)=x^5+3x^2-4x+2`

Required

Number of positive real zeros

Using Descartes rule of signs;

We write out the signs in front of each term;

Sign = + + - +

Count the number of times the sign alternate; i.e. from positive to negative and from negative to positive

From positive to negative, we have: 1 (i.e. + - )

From negative to positive, we have: 1 (i.e. - +)

Add up the count

`count = 1+1`

`count = 2`

Hence, the number of positive real zeros is 2 or 0