Equations and results involving double angle formulae
1. I would like to know if this is correct:
where x is an element of 0 and 360 (2pi in radians)
2. I would like to know where to continue in this question:
...I don't really know where to go from here and how to find angles for x.
3. I am being introduced to product and sum formulas and I don't know how to tackle the questions.
Find the exact value of sin2x, cos2x.
The extra formulas given for sinx and cosx are:
I know all the normal ones like sin2x=2sinxcosx etc., just not how to apply them.
If you could help me out here that would be great :D