[texhax] Error Messages

[Sophia Saucedo]

Dear Support,

Please advise what the following error messages mean and/or require to fix:

LaTex Warning: Reference 'infinite' on page 10 undefined on input line 732
LaTex Warning: Reference 'betaline' on page 10 undefined on input line 732
LaTex Warning: Citation "redbook' on page 10 undefined on input line 737

[10]
!Missing $ inserted.
<inserted text>
	4
1.762\cap
	(\beta \beta') \ne$

?

Sincerely
Sophia Saucedo