mathfail

Dictionary of Definitions of Terms Commonly Used in Math Lectures

CLEARLY:
I don’t want to write down all the “in- between” steps.

TRIVIAL:
If I have to show you how to do this, you’re in the wrong class.

OBVIOUSLY:
I hope you weren’t sleeping when we discussed this earlier, because I refuse to repeat it.

RECALL:
I shouldn’t have to tell you this, but for those of you who erase your memory tapes after every test…

WLOG (Without Loss Of Generality):
I’m not about to do all the possible cases, so I’ll do one and let you figure out the rest.

CHECK or CHECK FOR YOURSELF:
This is the boring part of the proof, so you can do it on your own time.

SKETCH OF A PROOF:
I couldn’t verify all the details, so I’ll break it down into the parts I couldn’t prove.

HINT:
The hardest of several possible ways to do a proof.

SOFT PROOF:
One third less filling (of the page) than your regular proof, but it requires two extra years of course work just to understand the terms.

ELEGANT PROOF:
Requires no previous knowledge of the subject matter and is less than ten lines long.

SIMILARLY:
At least one line of the proof of this case is the same as before.

CANONICAL FORM:
4 out of 5 mathematicians surveyed recommended this as the final form for their students who choose to finish.

BY A PREVIOUS THEOREM:
I don’t remember how it goes (come to think of it I’m not really sure we did this at all), but if I stated it right (or at all), then the rest of this follows.

TWO LINE PROOF:
I’ll leave out everything but the conclusion, you can’t question ’em if you can’t see ’em.

BRIEFLY:
I’m running out of time, so I’ll just write and talk faster.

LET’S TALK THROUGH IT:
I don’t want to write it on the board lest I make a mistake.

PROCEED FORMALLY:
Manipulate symbols by the rules without any hint of their true meaning (popular in pure math courses).

QUANTIFY:
I can’t find anything wrong with your proof except that it won’t work if x is a moon of Jupiter.

PROOF OMITTED:
Trust me, It’s true.

Thanks to Calculus Humor for this submission!

Source: http://www.calculushumor.com/3/post/2012/06/dictionary-of-definitions-of-terms-commonly-used-in-math-lectures.html

Einstein’s Puzzle

This is the kid friendly version of Einstein’s puzzle. It is claimed that only 2% of the world population can solve the puzzle! (and Einstein supposedly invented the original puzzle, though I have my doubts).

Suppose there are five houses of different colors next to each other on the same street. There are also five children who each live in one of these houses (with each child not living with the other four). Every child has a single favorite drink, a single favorite food, and also has one pet.

1. Peter lives in the red house.
2. Mary has a dog.
3. Linus drinks tea.
4. The green house is just to the left of the white one.
5. The child in the green house drinks lemonade.
6. The child who likes cookies has birds.
7. The child in the yellow house likes chocolate.
8. The child in the middle house drinks milk.
9. Emma lives in the first house.
10. The child who likes sweets has a neighbor with a cat.
11. The child who likes chewing-gum drinks apple juice.
12. The child who has a horse lives next to the child who likes chocolate.
13. Anna likes cake.
14. Emma lives next to the blue house.
15. The child who likes sweets lives next to the child who drinks water.

QUESTION: Who has fish?

Bonus: Determine everything you can about each person and their favorite things.

Source: http://zensteph.blogspot.ca/2012/09/einstein-riddle.html