Go Back   TestMagic Forums > Freestyle forum > Lounge
Register FAQForum Rules Members List Calendar Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Display Modes
Old 03-08-2008, 09:38 AM   #1 (permalink)
reactor
only Loeb spaces!

Moderator
 
reactor's Avatar
 
Join Date: Dec 2004
Posts: 2,072
reactor is served tea by TestMagic Inner Circle initiates.reactor is served tea by TestMagic Inner Circle initiates.reactor is served tea by TestMagic Inner Circle initiates.reactor is served tea by TestMagic Inner Circle initiates.reactor is served tea by TestMagic Inner Circle initiates.reactor is served tea by TestMagic Inner Circle initiates.
How to write a lazy proof (in mathematics)

You too can write a lazy proof! Just use at least one of the following phrases in a key point of your proof.
For an ultra-lazy proof use one of the phrases with an asterisk.

1) It is easy to see that...
2) Obviously...
3) Immediate. *
4) ...and the result follows.
5) As a result, we find that...
6) One easily verifies that...
7) The proof is left to the reader. *
8) The proof is left as an exercise.*
9) ....and the X theorem completes the proof.
10) Clearly...
11) It can be shown that...
12) Trivially...
13) The proof is standard.

Any additions are welcome!
(but you have to have actually seen the phrase used in a book or a lecturer's notes)
_ _ _ _ SIG _ _ _ _
"It's easy to have faith in yourself and have discipline when you're a winner, when you're number one. What you've got to have is faith and discipline when you're not yet a winner." Vince Lombardi

How to write a lazy proof

Teaching yourself how to prove

Since 2004 Reactor features (also) at:
Econometric Analysis, 5th Edition ERRATA

Last edited by reactor : 05-13-2008 at 09:54 PM.
reactor is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!Google Bookmark this Post!Reddit!
Reply With Quote
Old 03-08-2008, 01:24 PM   #2 (permalink)
TruDog
Studying for prelims...
 
Join Date: Aug 2006
Location: Midwest US
Posts: 506
TruDog is a TestMagic guru. Show your respect!TruDog is a TestMagic guru. Show your respect!
What about quite easily done?
_ _ _ _ SIG _ _ _ _
Attending University of Wisconsin-Madison
TruDog is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!Google Bookmark this Post!Reddit!
Reply With Quote
Old 03-08-2008, 02:13 PM   #3 (permalink)
asianeconomist
Loving the game
 
asianeconomist's Avatar
 
Join Date: Jul 2007
Location: Where the grass is greener
Posts: 757
asianeconomist is a TestMagic guru. Show your respect!
Quote:
Originally Posted by TruDog View Post
What about quite easily done?
Is that the jocular version of "quod erat demonstrandum".
_ _ _ _ SIG _ _ _ _
The Pens have been lifted and the Pages have dried. - At Tirmidhee.
asianeconomist is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!Google Bookmark this Post!Reddit!
Reply With Quote
Old 03-08-2008, 02:18 PM   #4 (permalink)
reactor
only Loeb spaces!

Moderator
 
reactor's Avatar
 
Join Date: Dec 2004
Posts: 2,072
reactor is served tea by TestMagic Inner Circle initiates.reactor is served tea by TestMagic Inner Circle initiates.reactor is served tea by TestMagic Inner Circle initiates.reactor is served tea by TestMagic Inner Circle initiates.reactor is served tea by TestMagic Inner Circle initiates.reactor is served tea by TestMagic Inner Circle initiates.
Quote:
Originally Posted by TruDog View Post
What about quite easily done?
Sounds good and I think that some of my lecturers use it often but I have not seen it written (yet).
_ _ _ _ SIG _ _ _ _
"It's easy to have faith in yourself and have discipline when you're a winner, when you're number one. What you've got to have is faith and discipline when you're not yet a winner." Vince Lombardi

How to write a lazy proof

Teaching yourself how to prove

Since 2004 Reactor features (also) at:
Econometric Analysis, 5th Edition ERRATA
reactor is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!Google Bookmark this Post!Reddit!
Reply With Quote
Old 03-08-2008, 02:20 PM   #5 (permalink)
reactor
only Loeb spaces!

Moderator
 
reactor's Avatar
 
Join Date: Dec 2004
Posts: 2,072
reactor is served tea by TestMagic Inner Circle initiates.reactor is served tea by TestMagic Inner Circle initiates.reactor is served tea by TestMagic Inner Circle initiates.reactor is served tea by TestMagic Inner Circle initiates.reactor is served tea by TestMagic Inner Circle initiates.reactor is served tea by TestMagic Inner Circle initiates.
Quote:
Originally Posted by asianeconomist View Post
Is that the jocular version of "quod erat demonstrandum".
nope. quod erat demonstrandum stands for "which was to be shown" and concludes a proof without making it less clear.
_ _ _ _ SIG _ _ _ _
"It's easy to have faith in yourself and have discipline when you're a winner, when you're number one. What you've got to have is faith and discipline when you're not yet a winner." Vince Lombardi

How to write a lazy proof

Teaching yourself how to prove

Since 2004 Reactor features (also) at:
Econometric Analysis, 5th Edition ERRATA
reactor is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!Google Bookmark this Post!Reddit!
Reply With Quote
Old 03-10-2008, 04:40 PM   #6 (permalink)
buckykatt
TestMagic Guru-in-Training
 
buckykatt's Avatar
 
Join Date: May 2007
Location: US
Posts: 895
buckykatt is a TestMagic guru. Show your respect!buckykatt is a TestMagic guru. Show your respect!
We can also "assume without loss of generality" or "to exclude trivial cases assume"... That's only a little lazy, though, I guess.
_ _ _ _ SIG _ _ _ _
"It's like a nerd watering hole in the savanna!" - econphilomath
buckykatt is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!Google Bookmark this Post!Reddit!
Reply With Quote
Old 03-17-2008, 05:15 PM   #7 (permalink)
buckykatt
TestMagic Guru-in-Training
 
buckykatt's Avatar
 
Join Date: May 2007
Location: US
Posts: 895
buckykatt is a TestMagic guru. Show your respect!buckykatt is a TestMagic guru. Show your respect!
I thought of another half-lazy one: "For specificity assume..." (e.g., if proving something about a monotonic function, assume that it is increasing)
_ _ _ _ SIG _ _ _ _
"It's like a nerd watering hole in the savanna!" - econphilomath
buckykatt is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!Google Bookmark this Post!Reddit!
Reply With Quote
Old 03-19-2008, 05:51 AM   #8 (permalink)
wolf87
Eager!
 
wolf87's Avatar
 
Join Date: May 2006
Location: Boston, MA
Posts: 57
wolf87 's dreams are becoming reality.
4 & 5 are my favorites, along with "WLOG, take ... . All other cases are trivial/analogous."
You also have to love the technique, especially common in Rudin, of citing 10+ numbered theorems in a sentence or two, writing one or two expressions, and stating that the desired consequence follows easily.
wolf87 is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!Google Bookmark this Post!Reddit!
Reply With Quote
Old 03-19-2008, 08:50 PM   #9 (permalink)
Oikos-nomos
Eager!
 
Oikos-nomos's Avatar
 
Join Date: Sep 2007
Posts: 45
Oikos-nomos 's dreams are becoming reality.
A good one that i hate is "...and with some simple algebraic manipulations we have..." , it usually means that you have to write half proof by yourself...
Oikos-nomos is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!Google Bookmark this Post!Reddit!
Reply With Quote
Old 04-20-2008, 09:46 AM   #10 (permalink)
EconCandidate
At Wisconsin-Madison
 
Join Date: Sep 2006
Posts: 139
EconCandidate radiates success.
10) Clearly ....(whatever they wanted to prove)
11) It can be shown that ....(yes, but not by me)
_ _ _ _ SIG _ _ _ _
Currently at Wisconsin-Madison
EconCandidate is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!Google Bookmark this Post!Reddit!
Reply With Quote
Reply


Thread Tools
Display Modes

What you can do
You cannot post new threads
You cannot post replies
You cannot post attachments
You cannot edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT. The time now is 01:24 AM.

Contact TestMagic   TestMagic Forums      Archive   

Link to TestMagic   TestMagic Locations   Legal   Privacy

Partner Sites: GMAT Sentence Correction   SAT 2400

Content Relevant URLs by vBSEO 3.0.0
Copyright © 1998-2008 TestMagic
Ad Management by RedTyger

Scroll Up