Also, if you have tried a question for yourself then present evidence that this is true.
Then interact with answerers if they give you any feedback or answer.
WE are here to help you learn. By posting multiple questions at once and NOT offereing ANY of your own thoughts on any of them then you are asking us to do your homework for you. You are presenting no evidence that you are trying to actually learn from us.
Can't you do ANY of this? Do you have some ideas?
Please just ask one question per post.
Look at the first thread in the sticky notes headed "Some Guidelines for question askers".
This question is being locked. You need ask one at a time.
Are you sure that all the brackets are in the right place?
let x= cosθ
solve it as a quadratic. (for x)
then sove for theta.
WE are not here to do your homework OR your quiz for you.
How about you tell us what you got for each letter.
Most of us here will be more cooperative with helping you see errors than in doing it all for you.
The smallest is 0
which ones can you eliminate? Why?
+118738 
