Simplify \(\frac{4a^2 - 49b^2}{2a^2 - 5ab - 7b^2}\)
If cot \(\theta\) = \(\frac{x}{y}\), find cosec\(\theta\)
If \(\cos^2 \theta + \frac{1}{8} = \sin^2 \theta\), find \(\tan \theta\).