iran-konkur 2020 Q112

iran-konkur · Other · konkur-riazi_1399_specialized_old-curriculum Standard trigonometric equations Solve trigonometric equation for solutions in an interval
112. The sum of the solutions of the equation $\tan(3x)\tan(x) = 1$ in the interval $[\pi, 2\pi]$ is:
$$5\pi \quad (1) \qquad 6\pi \quad (2) \qquad \frac{9\pi}{2} \quad (3) \qquad \frac{11\pi}{2} \quad (4)$$
\textbf{112.} The sum of the solutions of the equation $\tan(3x)\tan(x) = 1$ in the interval $[\pi, 2\pi]$ is:

$$5\pi \quad (1) \qquad 6\pi \quad (2) \qquad \frac{9\pi}{2} \quad (3) \qquad \frac{11\pi}{2} \quad (4)$$