Answer
$0.39$
Work Step by Step
1. Graph the function $y=cos(3x)-x$ as shown in the figure.
2. If $y=0$, then $cos(3x)=x$ so the x-intercepts give the solutions for the equation.
3. Based on the graph, within the interval of $[0,\pi]$ there is only one x-intercept at $x=0.39$
