\( \begin{array}{cc}\cot \theta=\frac{3}{4} & \text { and } \pi<\theta<\frac{3 \pi}{2} \\ \sin \theta=\quad & \sin (2 \theta)= \\ \operatorname{coc} \theta=\quad & \cos (2 \theta)= \\ \cos \theta= & \tan (2 \theta)= \\ \sec \theta= & \cos \left(\frac{\theta}{2}\right)= \\ \tan \theta= & \tan \left(\frac{\theta}{2}\right)=\end{array} \)
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To solve this problem, we first need to extract information about \(\theta\) given that \(\cot \theta = \frac{3}{4}\) and that \(\theta\) lies in the third quadrant (\(\pi < \theta < \frac{3\pi}{2}\)). Since \(\cot \theta\) is defined as \(\frac{\cos \theta}{\sin \theta}\), we can find \(\sin \theta\) and \(\cos \theta\) using the ratios of the sides of a right triangle. From \(\cot \theta = \frac{3}{4}\): - Let the adjacent side be 3 and the opposite side be 4. - Using the Pythagorean theorem, the hypotenuse \(r\) becomes: \[ r = \sqrt{3^2 + 4^2} = \sqrt{9 + 16} = \sqrt{25} = 5. \] In the third quadrant: \[ \sin \theta = -\frac{4}{5} \quad \text{and} \quad \cos \theta = -\frac{3}{5}. \] Now we can compute the other trigonometric functions needed. 1. \(\sin(2\theta) = 2\sin\theta\cos\theta\): \[ \sin(2\theta) = 2\left(-\frac{4}{5}\right)\left(-\frac{3}{5}\right) = 2 \cdot \frac{12}{25} = \frac{24}{25}. \] 2. \(\csc \theta = \frac{1}{\sin \theta} = -\frac{5}{4}\). 3. \(\cos(2\theta) = \cos^2\theta - \sin^2\theta = \left(-\frac{3}{5}\right)^2 - \left(-\frac{4}{5}\right)^2\): \[ \cos(2\theta) = \frac{9}{25} - \frac{16}{25} = -\frac{7}{25}. \] 4. \(\tan(2\theta) = \frac{\sin(2\theta)}{\cos(2\theta)}\): \[ \tan(2\theta) = \frac{\frac{24}{25}}{-\frac{7}{25}} = -\frac{24}{7}. \] 5. \(\sec \theta = \frac{1}{\cos \theta} = -\frac{5}{3}\). 6. \(\tan \theta = \frac{\sin \theta}{\cos \theta} = \frac{-\frac{4}{5}}{-\frac{3}{5}} = \frac{4}{3}\). 7. To find \(\cos\left(\frac{\theta}{2}\right)\) and \(\tan\left(\frac{\theta}{2}\right)\): Using the half-angle formulas: \[ \cos\left(\frac{\theta}{2}\right) = \sqrt{\frac{1+\cos\theta}{2}} = \sqrt{\frac{1 - \frac{3}{5}}{2}} = \sqrt{\frac{2}{5}} = \frac{\sqrt{10}}{5}. \] \[ \tan\left(\frac{\theta}{2}\right) = \frac{1 - \cos\theta}{\sin\theta} = \frac{1 - \left(-\frac{3}{5}\right)}{-\frac{4}{5}} = \frac{\frac{8}{5}}{-\frac{4}{5}} = -2. \] Combining everything, we have the following values: \[ \begin{array}{cc} \sin \theta = -\frac{4}{5} & \sin (2\theta) = \frac{24}{25} \\ \csc \theta = -\frac{5}{4} & \cos (2\theta) = -\frac{7}{25} \\ \cos \theta = -\frac{3}{5} & \tan (2\theta) = -\frac{24}{7} \\ \sec \theta = -\frac{5}{3} & \cos\left(\frac{\theta}{2}\right) = \frac{\sqrt{10}}{5} \\ \tan \theta = \frac{4}{3} & \tan\left(\frac{\theta}{2}\right) = -2. \end{array} \]