Answer
$\theta=1.19+k\pi$
Six example solutions for $k=0,\pm1,\pm2,3$:
$-5.09, -1.95, 1.19, 4.33, 7.47, 10.61$
Work Step by Step
Given $tan\theta=2.5$, use a calculator,
we can findone $\theta$ values in $[0,\pi],$ as $\theta=1.19$
and the general solutions are $\theta=1.19+k\pi$
where $k$ is any integer. Six example solutions for $k=0,\pm1,\pm2,3$:
$-5.09, -1.95, 1.19, 4.33, 7.47, 10.61$
