My Math Forum Need help with partial function problem.

 Calculus Calculus Math Forum

 September 11th, 2017, 03:30 PM #1 Newbie   Joined: Jan 2017 From: USA Posts: 11 Thanks: 0 Need help with partial function problem. It's a problem from discrete math, not calculus. I don't know where else to post it though. Can someone please help me understand what exactly this question is asking me to do? "Show that a partial function from A to B can be viewed as a function f* from A to B U {u}, where u is not an element of B and f*(a) = {f(a) if a belongs to the domain of definition of f, OR u if f is undefined at a}" I can see that it makes sense, but I don't know how to show that, or how to solve this problem. Please help. Last edited by skipjack; September 11th, 2017 at 04:40 PM.
 September 11th, 2017, 05:01 PM #2 Global Moderator   Joined: Dec 2006 Posts: 19,188 Thanks: 1648 It doesn't make sense to me - mainly because it's vague. What does "viewed as" mean? It would seem that the partial function is named f, but the problem doesn't explicitly say so - it just refers to f without explaining what f is. For it to make a little sense, A and B need to be sets, but the problem doesn't explicitly state that they are. If they are, a partial function from A to B is simply a function from C to B, where C is a subset of A. This definition doesn't require that C is known. Without a definition of "viewed as", it's impossible to make any further progress with this problem.
September 11th, 2017, 05:16 PM   #3
Newbie

Joined: Jan 2017
From: USA

Posts: 11
Thanks: 0

Quote:
 Originally Posted by skipjack It doesn't make sense to me - mainly because it's vague. What does "viewed as" mean? It would seem that the partial function is named f, but the problem doesn't explicitly say so - it just refers to f without explaining what f is. For it to make a little sense, A and B need to be sets, but the problem doesn't explicitly state that they are. If they are, a partial function from A to B is simply a function from C to B, where C is a subset of A. This definition doesn't require that C is known. Without a definition of "viewed as", it's impossible to make any further progress with this problem.
A and B are sets. It doesn't say how "viewed as" is defined

 September 11th, 2017, 05:24 PM #4 Global Moderator   Joined: May 2007 Posts: 6,540 Thanks: 591 https://en.wikipedia.org/wiki/Analytic_continuation Above may be what you need.

 Tags function, partial, problem

 Thread Tools Display Modes Linear Mode

 Similar Threads Thread Thread Starter Forum Replies Last Post Happy Calculus 0 December 6th, 2014 04:34 AM Jhenrique Calculus 3 April 1st, 2014 03:46 PM robinhg Real Analysis 1 February 21st, 2014 01:11 PM lo2 Calculus 3 October 29th, 2012 01:23 PM remeday86 Differential Equations 0 August 26th, 2010 01:03 PM

 Contact - Home - Forums - Cryptocurrency Forum - Top