Answer
The work done by the force on the object is $0.5~J$
Work Step by Step
The area under the force versus displacement graph is equal to the work done by the force. We can find the area under the graph from $x = 0$ to $x = 3.0~m$:
$Area = 1.0~J+0.5~J-1.0~J = 0.5~J$
The work done by the force on the object is $0.5~J$.
