1. **Stating the problem:** We are given the quadratic polynomial $$f(x) = 2x^2 - 4x - 5$$ and asked to check if $$x = 3$$ is a root (nulpunkt) of $$f(x)$$. 2. **Formula used:** To check if $$x = 3$$ is a root, we evaluate $$f(3)$$. If $$f(3) = 0$$, then $$x=3$$ is a root. 3. **Evaluate $$f(3)$$:** $$f(3) = 2(3)^2 - 4(3) - 5$$ $$= 2 \times 9 - 12 - 5$$ $$= 18 - 12 - 5$$ $$= 6 - 5$$ $$= 1$$ 4. Since $$f(3) = 1 \neq 0$$, $$x=3$$ is **not** a root of $$f(x)$$. **Final answer:** $$x=3$$ is not a zero of $$f(x)$$ because $$f(3) = 1 \neq 0$$.