Answer
$-1$
Work Step by Step
$\int_{\pi/2}^{\pi} (\frac{sin(2x)}{2\cdot sinx}) dx=\int_{\pi/2}^{\pi} (\frac{2sinxcosx}{2\cdot sinx}) dx=\int_{\pi/2}^{\pi} (cosx) dx=[sinx]_{\pi/2}^{\pi}=[sin\pi]-[sin\frac{\pi}{2}]=0-1=-1$
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.