(a) Start with the equation:
\(\cot 2\theta + \cot \theta = 2\)
Using the identity \(\cot 2\theta = \frac{1 - \tan^2 \theta}{2\tan \theta}\), substitute into the equation:
\(\frac{1 - \tan^2 \theta}{2\tan \theta} + \frac{1}{\tan \theta} = 2\)
Combine the terms over a common denominator:
\(\frac{1 - \tan^2 \theta + 2}{2\tan \theta} = 2\)
Simplify:
\(\frac{3 - \tan^2 \theta}{2\tan \theta} = 2\)
Multiply through by \(2\tan \theta\):
\(3 - \tan^2 \theta = 4\tan \theta\)
Rearrange into a quadratic equation:
\(\tan^2 \theta + 4\tan \theta - 3 = 0\)
(b) Solve the quadratic equation \(\tan^2 \theta + 4\tan \theta - 3 = 0\) using the quadratic formula \(\tan \theta = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}\), where \(a = 1, b = 4, c = -3\):
\(\tan \theta = \frac{-4 \pm \sqrt{16 + 12}}{2}\)
\(\tan \theta = \frac{-4 \pm \sqrt{28}}{2}\)
\(\tan \theta = \frac{-4 \pm 2\sqrt{7}}{2}\)
\(\tan \theta = -2 \pm \sqrt{7}\)
Calculate \(\theta\) for \(\tan \theta = -2 + \sqrt{7}\):
\(\theta = \tan^{-1}(-2 + \sqrt{7}) \approx 0.573\)
Calculate \(\theta\) for \(\tan \theta = -2 - \sqrt{7}\):
\(\theta = \tan^{-1}(-2 - \sqrt{7}) \approx 1.783\)
Thus, the solutions are \(\theta \approx 0.573\) and \(\theta \approx 1.783\).