Answer:
1/2
Explanation:
The Rational Root Theorem says that any rational root has
1. a numerator that is a factor of the constant term
2. a denominator that is a factor of the leading coefficient (that's attached to the highest-power term)
Numerator:
![\pm 1](https://img.qammunity.org/2022/formulas/mathematics/college/29md7onqxtyb65whqwnijbpstxt4agznfz.png)
Denominator:
![\pm 2](https://img.qammunity.org/2022/formulas/mathematics/college/2r3ipcgol3wzq3mx5wdw0rqvlurk6lnpkr.png)
That means there are only two possible rational roots:
![\pm (1)/(2)](https://img.qammunity.org/2022/formulas/mathematics/college/tp918yndpa3ii9my6xzktmaz0sgncpcy6z.png)
Try them both by plugging them into the polynomial.
![2\left((1)/(2)\right)^3 + 3\left((1)/(2)\right)^2 -1= (1)/(4)+(3)/(4)-1 =0](https://img.qammunity.org/2022/formulas/mathematics/college/map2v9esi7e7qyd23esfrz7iynewvwshbh.png)
Aha! The negative one-half value does not produce 0