Logic...

Ok I'm trying to mug for my first Math test this coming Friday now... Its been years since I last took an academic test of any kind so they seem kind of alien... Trying to read my textbook now and make sense of formal logic, lolx... It can be quite fun in a way, if only I could understand what I'm studying... Meanwhile, more tests are scheduled next wk in wk 7 and oso in wk 9... Gosh, I think I forgot wad its like to take a test liao =/

CONTRAPOSITIVE:

"If a vehicle is a car it has 4 wheels" is logically equivalent to "If a vehicle does not have 4 wheels it is not a car"

"If I am broke I will not have money to buy clothes" is logically equivalent to "If I have money to buy clothes I am not broke"

"If I am at home I will be slacking" is logically equivalent to "If I am not slacking I will not be at home"

U get the idea? LOL

Can be quite intuitive actually, and prob uses much of our common sense...

N can u believe that all of the above sentences can be expressed in mathematical notation, as in symbols?

Random Math Jokes

1. There is an engineer, a physicist, and a mathematician all walking down a road in the country. All of a sudden a sheep farmer calls them over to the nearby field where he tells them that he will pay a significant sum of money to the person who can build a fence to enclose his sheep using the least amount of fencing material.

The engineer goes first and builds a circle around the sheep and reasons that it is the least amount of material because it is a circle. The physicist goes next and builds an infinitely large circle around the sheep and shrinks it down to fit closely around them. The mathematician pauses, looks around, then builds a circle around himself and says, "I define that I am outside the fence..."


2. Person discussing his lack of math knowledge:
“Heavens! I don't even know what's the difference
between the radius and the diameter of a circle!
What's the difference between the radius & the diameter?”
The quick-thinking professor:
The radius!


3. A Mathematician, a Biologist and a Physicist are sitting in a street cafe watching people going in and coming out of the house on the other side of the street. First they see two people going into the house. Time passes. After a while they notice three persons coming out of the house.
The Physicist: "The measurement wasn't accurate."
The Biologist: "They have reproduced."
The Mathematician: "If now exactly 1 person enters the house then it will be empty again."