Give the general solutions of the following equations
- \(2\sin 3\theta - 7 \cos 2\theta + \sin \theta + 1 = 0\),
How might we reduce the number of different multiples of \(\theta\)?
Can we turn the LHS into a function of \(\sin \theta\) alone, or of \(\cos \theta\) alone?
- \(\cos\theta - \sin 2\theta + \cos 3\theta - \sin 4\theta = 0\).
How can we simplify an expression like \(\cos A + \cos B\)? Are there any identities that could help us?