JAMB 1987 · UME · Q25

A cubic function $f(x)$ is specified by the graph shown. The values of the independent variable for which the function vanishes are

Worked solution (try it first)

A function vanishes where its value is 0, that is, where the curve meets the $x$ -axis.
The graph crosses the $x$ -axis at $x = -1$ , $x = 0$ and $x = 1$ .
So the values are $-1, 0, 1$ , option A.