Covering of the orthogonal group

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Jason Bennett
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Homework Statement
see title
Relevant Equations
see below
Progress:πœ™:𝑂(3)β†’β„€2πœ“:𝑂(3)→𝑆𝑂(3)πœƒ:𝑂(3)/𝑆𝑂(3)β†’β„€2
πœ™(𝑂)=det(𝑂)

with π‘‚βˆˆπ‘‚(3), that way

πœ™(𝑂)↦{βˆ’1,1}β‰…β„€2,

where 1 is the identity element.Ker(πœ™) = {π‘‚βˆˆπ‘†π‘‚(3)|πœ™(𝑂)=1}=𝑆𝑂(3), since det(𝑂)=1 for π‘‚βˆˆπ‘†π‘‚(3).By the multiplicative property of the determinant function, πœ™ = homomorphism.
***What is the form of the canonical homomorphism (πœ“) in this case?I'm used to the coset language,i.e. πœ“:𝐺→𝐺/Ker(πœ™)

with πœ“(𝑔)=𝑔𝐾 for 𝐾=ker(πœ™)

If this were settled, then πœƒ is an isomorphism by the isomorphism theorem.
 
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Please use ## to edit your Latex, it is not rendering anything understandable.
 
The basic idea can be seen in your solution, but it's written in an unpleasant way. E.g. you shouldn't use ##O## as a matrix, since it looks like ##0##. Try to sort your thoughts: statement - deductions - conclusion.
Have a look at:
https://www.physicsforums.com/insights/how-most-proofs-are-structured-and-how-to-write-them/
And for the use of LaTeX see:
https://www.physicsforums.com/help/latexhelp/
What do ##O(3)## and ##SO(3)## mean?
This means: which of several possible definitions do you use?

Then consider ##\det## and explain, why it is a group homomorphism.
What is its image?
Why is it surjective?
What is its kernel?

Conclude the statement as an application of the isomorphism theorem.