Find all solutions for cosθ = √2 - cosθ?

Question

anonymous · Answer

Help would be awesome! If I could even just get the formula to use, it would be great help. I'm really lost. Thank you.

solomonzelman · Answer

cosθ = √2 - cosθ     add cosθ  to both sides
2cosθ=√2   divide both sides by 2
cosθ=√2/2

What angle is this ?
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anonymous · Answer

@SolomonZelman - That's what I had! Thank you!  We are supposed to convert the answer into radians, however.. Let me see. Would you mind checking my work afterwards?

solomonzelman · Answer

If I am online, and if I am good enough at math, b/c I am not.

solomonzelman · Answer

I will try if I am on.

anonymous · Answer

@solomonZelman - cosθ = √2 - cosθ
2cosθ=√2 
cosθ=√2/2
θ = cos-1(√2/2)
θ = π/4 + 2πn

solomonzelman · Answer

After you got 
cosθ=√2/2
and after looking at my post you will probably get it.

anonymous · Answer

OR θ = 45º + 360ºn

solomonzelman · Answer

Yes, so... the answer is ?

solomonzelman · Answer

the theta = ?

anonymous · Answer

That is the answer.

anonymous · Answer

I just figured it out :)

anonymous · Answer

I checked it and it's right. We may not be thinking about the same subject material.

solomonzelman · Answer

but one thing answer, very very short. What is it ?

anonymous · Answer

That is the answer.. θ = 45º + 360ºn

solomonzelman · Answer

I would just say that it is 45º but either way.

anonymous · Answer

Oh. I know, but my teacher wants it this way. I didn't mean to come off as rude. :-) Thanks for your help nonetheless.