My Math Forum understanding quotient topology

 Topology Topology Math Forum

 March 20th, 2018, 10:01 PM #1 Newbie   Joined: Oct 2017 From: sweden Posts: 20 Thanks: 0 understanding quotient topology Let $h$ be a (real-valued) continuous function on some closed interval $[c,d].$ Let, $\lambda =\min_{[c,d]}h$ and $\gamma = \max_{[c,d]}h$ . Also, $h$ can be considered as a surjective map (onto) from $[c,d] \rightarrow [\lambda,\gamma]$. **Question** How can one show that if $[c,d]$ has the usual topology, then the quotient topology on $[\lambda,\gamma]$ is also the usual topology ? I am genuinely frustrated because this is an example from the quotient topology chapter, but the solution to this the author gave I cannot understand at all. I would really appreciate some help. Note the quotient topology I am working with here is given by: a quotient topology on $Y$ is defined to be $T_Y=\{ V\subset Y : f^{-1}(V) \in T_X\}$,where $f:X\rightarrow Y$, and a topological space $X$ with topology $T_X.$ Last edited by heinsbergrelatz; March 20th, 2018 at 10:04 PM.
 March 20th, 2018, 10:04 PM #2 Senior Member   Joined: Aug 2012 Posts: 2,193 Thanks: 645 Quotient with respect to what equivalence relation?
 March 20th, 2018, 10:05 PM #3 Newbie   Joined: Oct 2017 From: sweden Posts: 20 Thanks: 0 Sorry I just edited my post to the quotient topology definition I am using.
 March 21st, 2018, 04:47 AM #4 Senior Member   Joined: Oct 2009 Posts: 752 Thanks: 257 Can you show h is closed? Hint: the domain is compact.
 March 21st, 2018, 05:38 AM #5 Newbie   Joined: Oct 2017 From: sweden Posts: 20 Thanks: 0 I am sorry my topplogy is very weak. My midterm is 2 days from now, and this is one of the past problems. Can you show me how to do this, I really have to understand how in a short time and the solution manual is not helping one bit.

 Thread Tools Display Modes Linear Mode

 Similar Threads Thread Thread Starter Forum Replies Last Post aminea95 Topology 2 January 20th, 2018 07:36 AM LordofthePenguins Topology 8 July 9th, 2013 12:44 PM vercammen Topology 1 October 19th, 2012 11:06 AM lorereds Topology 0 September 7th, 2011 06:13 AM genoatopologist Topology 0 December 6th, 2008 10:09 AM

 Contact - Home - Forums - Cryptocurrency Forum - Top