Monday, May 5, 2014

Quadratic

I looked up "Parabolas in Real Life" on Google and right away I see the very famous St. Louis Arch, also called the Gateway Arch. I knew I just had to do some research on the construction of the arch, just look at it! It's absolutely amazing, and a perfect parabola (or so I first though)! I couldn't begin to understand how the managed to build such an odd structure because it looks as if the during the construction the entire thing would come crashing down. Apparently though, the arch isn't a parabola at all, it's refereed to as an inverted catenary. A catenary is defined as the "curve formed when you allow a chain or cable to hang from its two ends under its own weight", so in an inverted catenary is one in which the curve hangs up instead of down. 


By observing the construction below I was able to conclude that each leg had to essentially support its own weight until they came close to touching each other. In the 5th picture we see a brace added to the middle that made it so neither side would collapse. Wedges, that could be compared to triangular wedges of cheese, were stacked one on top of the other until the two curves finally met in the middle. There was lots of math involved in the creation of the Gateway and although I don't really understand a lot of it....
The geometric form of the structure was set by mathematical equations provided to Saarinen by Hannskarl Bandel. Bruce Detmers and other architects expressed the geometric form in blueprints with this equation:[72]
y = A \left( \cosh \frac {Cx}{L} - 1 \right) \quad\Leftrightarrow\quad x = \frac {L}{C} \cosh^{-1} \left( 1 + \frac {y}{A} \right),
with the constants
A = \frac {f_c} {Q_a/Q_t - 1} = 68.7672
C = \cosh^{-1} \frac {Q_b}{Q_t} = 3.0022
where fc = 625.0925 ft (191 m) is the maximum height of centroid, Qb = 1,262.6651 sq ft (117 m2) is the maximum cross sectional area of arch at base,Qt= 125.1406 sq ft (12 m2) is the minimum cross sectional area of arch at top, and L = 299.2239 ft (91 m) is the half width of centroid at the base.
(copied from wikipedia)
it is clear that without a lot of time and thought this project would have gone nowhere. It's very cool to see how such a daunting project to light and how it was made!

Sequence of nine photos documenting the rise of the Gateway Arch in St. Louis, Missouri.

Sunday, April 6, 2014

Math in Jobs

There's one question that is always asked during math class, "Are we ever actually going to use this stuff?" That's one question I've always wondered about. Why are we learning such weird theories, formulas and equations? What good will it do us? How come it is so necessary in our lives? Well, for my blog I decided to research a couple of obscure jobs that require mathematics in order to see why it is so important in our academic curriculum.

The Actuary
With a little help from Google, I was able to find out how interesting the job of an actuary is. They work with predicting and analyzing the consequences of risks. They are a financial planner of sorts. Actuaries use math, financial studies and statistics in order to predict what will happen in the future. For instance, after the event of a large hurricane an actuary's job is to guesstimate long term damage costs, and plan for future kinds of insurances that will need to be given to people living where the hurricane took place. By using math, we are sort of able to see the future!
   
The Cryptologist
Cryptology is the study of ways we can communicate secretly in the presence of other parties. Not only do cryptologists create codes to be used for secrecy, but they also break codes they intercept. A great deal of math and puzzle solving skills is used in cryptology. A crpytologist's main method of breaking a code involves using algorithms. An algorithm is a step-by-step procedure of calculations. They use algorithms to narrow down the different types of code that could could possibly apply to the encrypted message. Without cryptology our greatest secrets and messages would fall straight into enemy hands!
  



Tuesday, February 18, 2014

Pascal's Triangle

There are many patterns in Pascal's Triangle. One of the most visible is the powers of 11. It goes like so:
1=11^0
11=11^1
1 2 1=11^2
1 3 3 1=11^3
1 4 6 4 1=11^4
1 5 10 10 5 1=11^5
1 6 15 20 15 6 1=11^6
1 7 21 35 35 21 7 1=11^7

So we all know that 11^2 is 121 but once the numbers start getting to the double digits like 1 7 21 and such we have to carry number over in order to get the correct answer. 11^7 is really 19487171. In order to get this answer from Pascal's Triangle we carry all of the tens to the next column. So from right to left- 1 7 1, now add the 2 from 21 to 5, 7, now add the 3 from 35 to 5, 8, now add the 3 from 35 to 1, 4, now add the 2 from 21 to 7, 9 1. 1 7 1 7 8 4 9 1. There we go!

Now for the other patterns in Pascal's Triangle. The sum of any given row is 2 to the rows number power. Example: Row 1= 1+1= 2^1, Row 2 = 1+2+1=2^2, so on and so forth.

Another pattern in the triangle that we have is Fibonacci's number. The pattern goes 1,1,2,3,5,8,13,21 you take the number you are given and at it to the last number to get your new number. In Pascal's Triangle if you make a sorta angled diagonal we get this pattern. First diagonal is 1. Second diagonal is 1. Third diagonal is 1+1=2. Fourth diagonal is 1+2=3. Continue.

There are probably many, many more patterns in Pascal's Triangle we just have to be willing to work it out far enough!

url.gif

url.png

Sunday, January 12, 2014

Math Humor

calvinmath4.jpg
I feel like a lot of people are like this. Hah!

algebra-cartoon.gif
Whenever we ask why this all matters.

This relates to the blog we did on %. This is the kind of stuff that tricks us everyday!

Percents. This reminds me of all the people that give the odds of winning the lottery and such.

Hilarious! "Most of"

Maybe something along the lines of "I'm allergic to math" would have worked just as well as this.

IMAGINARY!

Pretty sure this is true for rabbits.....

I can only imagine how hard it would be to write something like this.

CalvinMath.jpg
There are always reasons why Calvin can't do math.

I bet this would actually work.


http://mrart.wikispaces.com/Math+Cartoons

http://math.sfsu.edu/beck/quotes.html