Sunday, February 21, 2010
How Far Can Math Take Us?
The second portion of the cover story Online Extra: The NSA: Security in Numbers discussed the usage of numbers in terms of security. Baker discussed the NSA's role and how they use math to help figure out terrorist plots and other issues of security. One of the challenges the NSA faces manifests itself in recruiting its mathematicians. They are faced with competition from Google, Yahoo and other organizations. How are they managing? They offer a more quiet, stable lifestyle, which is especially more appealing to women. I thought it was interesting that they were looking for younger employees who did not know the company as well. I assumed they would want older, more experienced workers. I found the selection process quite interesting in that it is a contest which acts as somewhat of an advisory for their decisions.
The third portion Online Extra: Search Advertising by the Numbers discussed bidding on keywords. Baker specifically discussed Imran Khan and his involvement in E-Loan. Kahn makes sure those who are looking for his product will surely find it. Parts of this passage made it seem like math can often get a little bit too invasive, "It (numbers) enables marketers to track customer behavior, and replaces hunches with science." It may have just been the way I read into the article, but that sounds as though it could be problematic in terms of individual privacy issues. I also found the discussion of bidding on keywords and the science behind it a bit confusing.
How Much Math Do We Need to Know? summed up the different uses of Calculus, Algebra and Geometry, Statistics and Probablility, and Math Tools in different careers. Some of the associations are not as obvious as they seem, for example, advanced geometry is used not only in floor tiling but also in designing search engines. With the growing demand for mathematics based, or even just related professions, knowing your math might prove to be helpful. I guess calculus really will pay off in the long run!
How Math Transforms Industries discussed the specific uses of mathematics in many different fields, such as consulting, police and marketing and the media. Who knew a company could "turn written articles into bits of geometry and organize them in a virtual library?" and eventually these automatic systems could make editors obsolete. I found it amazing how much of a difference math has a potential of making on our society. We always talk about technology taking over life as we know it, but what about math?
Saturday, January 30, 2010
See Math
Sunday, January 24, 2010
Choices
2)
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3) Volume is an invertible function
4)
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5)
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a)(4/3)*3.141592654x^3
b)12.566375(x-1)+4.1887902
c)(x/(4*3.141592654/3))^(1/3)
d).09403455(x-4.1887902)+1
6) My point (1, 4.1887902)
slope of tangent line at f(1)=12.566375
slope of tangent line at f'(2.3562)= 0.09403455
12.566375*0.09403455=1
7)I chose to come to class on Virtual Wednesday because I feel as though I learn better in a classroom environment. It provides structure and an atmosphere in which it is easier for me to focus. The resources of Bru and my classmates are of great help when I don't completely understand a concept. Learning from Bru and my classmates in a classroom as opposed to an online classroom is a much more reliable method of learning for me and is a more concrete way to learn the material. I have the opportunity to ask questions and am provided with a structured and complete lesson.
Tuesday, January 19, 2010
Derivatives of Other Trigonometric Functions (Scribe Post for Monday's Class)
In the beginning of class, we reviewed a few topics from trigonometry including the reciprocal properties, the quotient properties and the Pythagorean Properties. Here are the slides from the notes we took in class. It also includes the derivations of the four other trig functions. Hope it helps!

I found the unit circle diagram for the Pythagorean Properties very helpful, but in case this is hard to read, here is a summary of the three types of properties:
#1: THE RECIPROCAL PROPERTIES:

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#2: THE QUOTIENT PROPERTIES:
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#3: THE PYTHAGOREAN PROPERTIES:
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Ok, so now onto the fun part, the derivatives of the other trig functions. In order to discover these derivatives, we used the quotient rule.
(Just in case you forgot, the quotient rule is the derivative of numerator times the denominator minus the numerator times the derivative of the denominator all divided by the denominator squared.)
So here are our the results of our derivations for the six trigonometric functions:
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In order for this to be true though, x must be in radians
Here are some of the memory aids we came up with in class:
- Derivatives of "co" functions have negative signs
-from Pythagorean Properties
+tanx goes with secx
+cotx goes with cscx
+sinx goes with cosx
Here is a short video I found helpful. It has a few examples:

http://www.slideshare.net/share/blogspot/116892
REMEMBER TOMORROW IS VIRTUAL WEDNESDAY. YOU CAN CHOSE WHETHER TO COME TO CLASS OR TO DEVELOP YOUR OWN VIRTUAL LESSON. The topic is: the derivative of inverse functions.
If you have any questions at all please feel free to leave a comment.
And the next scribe is..... drum roll please.... Beston
Here is the sample derivation for secant:
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Sunday, January 17, 2010
Anyone can learn anything, from anyone, anywhere, at anytime
Although I believe Web 2.0 is a useful resource in finding many different types of information, I do not believe it should be the sole informant. Schools and formal education, in my opinion are very important components of education. Teachers and classrooms encourage learning and focus. In addition, a student faculty relationship is created, predominantly one that pushes the students to complete their work to their best ability. Internet sources, on the other hand, can often provide distractions. Focus while on the Internet often requires control and restraint in terms of the distractions. I believe the Internet can and does provide a source to find anything from anyone anywhere at anytime, but schools and a formal education are also a necessity in order to create a balanced education.
Sunday, January 10, 2010
Product Rule
Or textbook clearly explained the definition of the derivative of a product of two functions. It also gave three examples in order to fully understand the product rule. The book includes both a mathematical and verbal explanation. The online explanation was similar in that it mathematically explained the product rule and gave multiple examples. I found the online explanation useful in that it explained the product rule in terms of f(x), g(x), and h(x), mathematically in multiple ways. I found the textbook explanation a bit easier to understand and visualize because of its verbal explanation.
Product Rule: Mathematical: If h(x)=f(x)g(x), then h'(x)= f'(x)g(x)+f(x)g'(x),
Verbally: The derivative of the function of the product of two functions is the derivative of the first function times the second function plus the first function times the derivative of the second.
Example:
f(x)=x4cos6x
f’(x)=4x3cos6x+x4(-sin6x)(6)
f’(x)=4x3cos6x-6x4sin6x