Tricky Sets and Trig Questions - Can You Solve Them?

[guynoone]

Hi, I just have three question and I'm wondering how to solve them.

The first one is a sets question and it is literally infuriating trying to even contemplate it. I've asked many other people how to solve and no one knows how. I was hoping there would be a few geniuses that solve it here

The other 2 are just trig questions. I have a feeling at the back of my head that I knew how to solve them, but that's it.

 

[tiny-tim]

Hi guynoone!

Why couldn't you just type them out?

To show that sin3x/(1 + cos3x) = tyan(3x/2), just write sin3x and cos3x in terms of functons of 3x/2.

 

[guynoone]

Why couldn't you just type them out?

I hate looking for the correct symbols. I also wanted to test out the new scanner :)

To show that sin3x/(1 + cos3x) = tyan(3x/2), just write sin3x and cos3x in terms of functons of 3x/2.

Sorry, my mind's a bit fuzzy. What happens to that +1 then?

 

[HallsofIvy]

Why don't you try what he suggested and then see what happens?
sin(3x)= sin(2(3x/2) and cos(3x)= cos(2(3x/2) so tiny-tim is suggesting you use the double angle formulas.