Predicate Logic and Popular Culture (Part 130): Chris Young

Let T(x,t) be the proposition “They think of x at time t.” Translate the logical statement

\forall t(T(\hbox{me},t) \Rightarrow T(\hbox{you},t)).

This sentence ends the chorus of this hit country duet by Chris Young and Cassadee Pope.

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Context: Part of the discrete mathematics course includes an introduction to predicate and propositional logic for our math majors. As you can probably guess from their names, students tend to think these concepts are dry and uninteresting even though they’re very important for their development as math majors.

In an effort to making these topics more appealing, I spent a few days mining the depths of popular culture in a (likely futile) attempt to make these ideas more interesting to my students. In this series, I’d like to share what I found. Naturally, the sources that I found have varying levels of complexity, which is appropriate for students who are first learning prepositional and predicate logic.

When I actually presented these in class, I either presented the logical statement and had my class guess the statement in actual English, or I gave my students the famous quote and them translate it into predicate logic. However, for the purposes of this series, I’ll just present the statement in predicate logic first.

Predicate Logic and Popular Culture (Part 129): Keith Urban

Let p be the proposition “Blue is your color.” Translate the logical statement

\lnot p.

This is the (grammatically incorrect) title of a recent popular country song by Keith Urban.

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Context: Part of the discrete mathematics course includes an introduction to predicate and propositional logic for our math majors. As you can probably guess from their names, students tend to think these concepts are dry and uninteresting even though they’re very important for their development as math majors.

In an effort to making these topics more appealing, I spent a few days mining the depths of popular culture in a (likely futile) attempt to make these ideas more interesting to my students. In this series, I’d like to share what I found. Naturally, the sources that I found have varying levels of complexity, which is appropriate for students who are first learning prepositional and predicate logic.

When I actually presented these in class, I either presented the logical statement and had my class guess the statement in actual English, or I gave my students the famous quote and them translate it into predicate logic. However, for the purposes of this series, I’ll just present the statement in predicate logic first.

Predicate Logic and Popular Culture (Part 128): The King and I

Let T(x,y,t) be the proposition “x trusts y at time t,” let E(x,t) be the proposition “x is on Earth at time t,” and let F(x) be the proposition “x is a fish.” Translate the logical statement

\lnot (\exists t \exists x \exists y T(x,y,t)) \Rightarrow \exists T \forall x \forall t \ge T (E(x,t) \Rightarrow F(x)).

This matches one of the King’s laments about how to rule wisely in The King and I.

 

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Context: Part of the discrete mathematics course includes an introduction to predicate and propositional logic for our math majors. As you can probably guess from their names, students tend to think these concepts are dry and uninteresting even though they’re very important for their development as math majors.

In an effort to making these topics more appealing, I spent a few days mining the depths of popular culture in a (likely futile) attempt to make these ideas more interesting to my students. In this series, I’d like to share what I found. Naturally, the sources that I found have varying levels of complexity, which is appropriate for students who are first learning prepositional and predicate logic.

When I actually presented these in class, I either presented the logical statement and had my class guess the statement in actual English, or I gave my students the famous quote and them translate it into predicate logic. However, for the purposes of this series, I’ll just present the statement in predicate logic first.

Predicate Logic and Popular Culture (Part 127): Hamilton

Let L(x) be the proposition “x is legal in New Jersey.” Translate the logical statement

\forall x L(x).

This translates as “Everything is legal in New Jersey,” one of the running gags in the hit musical Hamilton.

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Context: Part of the discrete mathematics course includes an introduction to predicate and propositional logic for our math majors. As you can probably guess from their names, students tend to think these concepts are dry and uninteresting even though they’re very important for their development as math majors.

In an effort to making these topics more appealing, I spent a few days mining the depths of popular culture in a (likely futile) attempt to make these ideas more interesting to my students. In this series, I’d like to share what I found. Naturally, the sources that I found have varying levels of complexity, which is appropriate for students who are first learning prepositional and predicate logic.

When I actually presented these in class, I either presented the logical statement and had my class guess the statement in actual English, or I gave my students the famous quote and them translate it into predicate logic. However, for the purposes of this series, I’ll just present the statement in predicate logic first.

Predicate Logic and Popular Culture (Part 126): Hamilton

Let W(x,t) be the proposition “You walk with x at time t.” Translate the logical statement

\lnot \exists t \forall x \lnot W(x,t).

The straightforward way of translating this into English is, “If you stand for nothing, then you’ll fall for anything,” one of the motifs (with a slightly different wording) of the hit musical Hamilton.

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Context: I recently taught discrete mathematics for the first time. Part of the discrete mathematics course includes an introduction to predicate and propositional logic for our math majors. As you can probably guess from their names, students tend to think these concepts are dry and uninteresting even though they’re very important for their development as math majors.

In an effort to making these topics more appealing, I spent a few days mining the depths of popular culture in a (likely futile) attempt to make these ideas more interesting to my students. In this series, I’d like to share what I found. Naturally, the sources that I found have varying levels of complexity, which is appropriate for students who are first learning prepositional and predicate logic.

When I actually presented these in class, I either presented the logical statement and had my class guess the statement in actual English, or I gave my students the famous quote and them translate it into predicate logic. However, for the purposes of this series, I’ll just present the statement in predicate logic first.

Predicate Logic and Popular Culture (Part 125): INXS

Let M(x) be the proposition “x is a man,” let W(x) be the proposition “x is with you,” and let K(x) be the proposition “I knew x.” Translate the logical statement

\forall x ((M(x) \land W(x)) \Rightarrow K(x)).

This matches the chorus of “Do Wot You Do” by INXS, which also was on one of the all-time best movie soundtracks.

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Context: This semester, I taught discrete mathematics for the first time. Part of the discrete mathematics course includes an introduction to predicate and propositional logic for our math majors. As you can probably guess from their names, students tend to think these concepts are dry and uninteresting even though they’re very important for their development as math majors.

In an effort to making these topics more appealing, I spent a few days mining the depths of popular culture in a (likely futile) attempt to make these ideas more interesting to my students. In this series, I’d like to share what I found. Naturally, the sources that I found have varying levels of complexity, which is appropriate for students who are first learning prepositional and predicate logic.

When I actually presented these in class, I either presented the logical statement and had my class guess the statement in actual English, or I gave my students the famous quote and them translate it into predicate logic. However, for the purposes of this series, I’ll just present the statement in predicate logic first.

Predicate Logic and Popular Culture (Part 124): High School Musical

Let W(x) be the proposition “I want to do x.” Translate the logical statement

W(\hbox{be with you}) \land \forall x ((x \ne \hbox{be with you}) \Rightarrow \lnot W(x)).

This matches the chorus of one of the songs from High School Musical 3.

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Context: This semester, I taught discrete mathematics for the first time. Part of the discrete mathematics course includes an introduction to predicate and propositional logic for our math majors. As you can probably guess from their names, students tend to think these concepts are dry and uninteresting even though they’re very important for their development as math majors.

In an effort to making these topics more appealing, I spent a few days mining the depths of popular culture in a (likely futile) attempt to make these ideas more interesting to my students. In this series, I’d like to share what I found. Naturally, the sources that I found have varying levels of complexity, which is appropriate for students who are first learning prepositional and predicate logic.

When I actually presented these in class, I either presented the logical statement and had my class guess the statement in actual English, or I gave my students the famous quote and them translate it into predicate logic. However, for the purposes of this series, I’ll just present the statement in predicate logic first.

Engaging students: Geometric sequences

In my capstone class for future secondary math teachers, I ask my students to come up with ideas for engaging their students with different topics in the secondary mathematics curriculum. In other words, the point of the assignment was not to devise a full-blown lesson plan on this topic. Instead, I asked my students to think about three different ways of getting their students interested in the topic in the first place.

I plan to share some of the best of these ideas on this blog (after asking my students’ permission, of course).

This student submission comes from my former student Zachery Hasegawa. His topic, from Precalculus: geometric sequences.

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How has this topic appeared in pop culture? (movies, TV, current music, video games, etc.)

Geometric sequences appear frequently in pop culture.  One example that immediately comes to mind is the movie The Happening starring Mark Wahlberg and Zoe Deschanel.  In the movie, there is a scene where a gentleman is trying to distract another woman from the chaos happening outside the jeep they’re traveling in.  He says to her “If I start out with a penny on the first day of a 31 day month and kept doubling it each day, so I’d have .01 on day 1, .02 on day 2, etc.  How much money will I have at the end of the month?” The woman franticly spouts out a wrong answer and the gentleman responds “You’d have over ten million dollars by the end of the month”.  The car goes on to crash just after that scene but as a matter of fact, you’d have exactly $10,737,418.20 at the end of the 31-day month.  This is an example of a geometric sequence because you start out with 0.01 and to get to the next term (day), you would multiply by a common ratio of 2.

 

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What interesting things can you say about the people who contributed to the discovery and/or the development of this topic?

Geometric sequences are popularly found in Book IX of Elements by Euclid, dating back to 300 B.C.  Euclid of Alexandria, a famous Greek mathematician also considered the “Father of Geometry” was the main contributor of this theory.  Geometric sequences and series are one of the easiest examples of infinite series with finite sums.  Geometric sequences and series have played an important role in the early development of calculus, and have continued to be a main case of study in the convergence of series.  Geometric sequences and series are used a lot in mathematics, and they are very important in physics, engineering, biology, economics, computer science, queuing theory, and even finance.

 

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How can technology (specifically Khan Academy/YouTube) be used to effectively engage students with this topic:

 

I really like the video that Khan Academy does on YouTube about Geometric Sequences.  This particular video is a very good introduction to Geometric Sequences because he explains the difference between Geometric Sequences and Series, which I thought to be helpful because I always got the two confused with each other.  Mr. Khan starts out by explaining what exactly a Geometric Sequence is. He describes a Geometric sequence as “A progression of numbers where each successive number is a fixed multiple of the one before it.” He goes on to give numerical examples to specifically show you what he means.  He explains that a1 is typically our first term; a2 is the second term, etc.  He then explains that to get from a1 to a2, you will multiply a1 by the “common ratio” usually represented by “r. For example, “3, 12, 48, 192” is a finite geometric sequence where the common ratio, r, is 4 because to go from 3 to 12 or from 12 to 48, you multiply by 4. He goes on to explain that a Geometric Sequence is a list (sequence) of numbers (terms) that are being multiplied by a common ratio and that a Geometric Series is the sum of the terms (numbers) in the Geometric Sequence.  Using the same numbers as from the Geometric Sequence above, the geometric series is “3+12+48+192”.

 

 

References:

 

 

 

 

Engaging students: Graphing parametric equations

In my capstone class for future secondary math teachers, I ask my students to come up with ideas for engaging their students with different topics in the secondary mathematics curriculum. In other words, the point of the assignment was not to devise a full-blown lesson plan on this topic. Instead, I asked my students to think about three different ways of getting their students interested in the topic in the first place.

I plan to share some of the best of these ideas on this blog (after asking my students’ permission, of course).

This student submission comes from my former student Perla Perez. Her topic, from Precalculus: graphing parametric equations.

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How can technology (YouTube, Khan Academy [khanacademy.org], Vi Hart, Geometers Sketchpad, graphing calculators, etc.) be used to effectively engage students with this topic? Note: It’s not enough to say “such-and-such is a great website”; you need to explain in some detail why it’s a great website.

 

Graphing calculators and online sketch pads can allow students to be able to visually see how parametric equations look like. Let’s say the teachers is just introducing parametric equations for the first time to his/her students. Since technology is advancing at a fast rate using an online sketchpad such as, http://www.sineofthetimes.org/the-art-of-parametric-equations-2/, allows student/anyone to explore without much thought. Using the sketch pad above, have students create different figures by moving the blue, green, and red slides. The figures represent can range from:

 

Have a couple student present a figure they like to the class and begin asking simple question like: Why did you chose this picture? Which slides did you use to get here? What did you observe of this sketch? What happens to the equations when you move one of the slides? After the last students shows their figure, bring the class together. Explain that the goal for the next few classes is to be able to graph similar graphs. Although the parametric equations on this sketchpad may be advanced for a high school pre-calculus class, this allows students to get a broader sense of where their high school education can grow.

 

Resources:

http://www.sineofthetimes.org/the-art-of-parametric-equations-2/

 

 

 

 

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What interesting things can you say about the people who contributed to the discovery and/or the development of this topic? (You might want to consult Math Through The Ages.)

 

Jules Lissajous (1822–1880) was a professor of mathematics in Lycée Saint-Louis from 1847 till 1874. During this time, though, he mainly focused on the study of vibrations and sound. It is because of him (mainly) that we can visually see sound. The way this was done was by parametric equations specially x=asin(w1t+z2), y=bsin(w2+z2), where a, b are amplitudes w1, w2 angular frequencies, z1, z2 phases, and t is time. Using this he was able to create, “patterns formed when two vibrations along perpendicular lines are superimposed”. To a high school student essentially resembles a coordinate plane. Even though he won the Lacaze Prize in 1867 for what many call, “beautiful experiments”, a man named Nathaniel Bowditch produced them using a compound pendulum in 1815. Even though the work isn’t new, Lissajous did his work independently. Jules has helped advanced our studies of not only math but in physics.

 

Resources:

http://www.hit.bme.hu/~papay/edu/Lab/Lissajous.pdf

http://www-groups.dcs.st-and.ac.uk/history/Biographies/Lissajous.html

http://www.s9.com/Biography/lissajous-jules-antoine/

 

 

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What interesting (i.e., uncontrived) word problems using this topic can your students do now? (You may find resources such as http://www.spacemath.nasa.gov to be very helpful in this regard; feel free to suggest others.)

 

Students in algebra learn how to graph a function in a coordinate plane as well as be able to solve for an equation from a graph. Before, students begin to graph parametric equations for the most have some understanding of what a parametric equation is, at least in most situations. To take the students to the next level and build on their understanding, interesting world problems such as the one below can help the process go more smoothly. This worksheet begins with something students should be able to complete and expand to what graphs of a parametric equations look like.

This word problem is:

Begin by having students fill the table out. Take a moment to check student’s results. Next, challenge the students to attempt to plot and describe the graph as asked in part b and c. From there on, the instructor can go over what these parts mean. This is a great way to start having student connect their knowledge of equations to a graph to even more topics in-depth.

 

Resources:

http://www.austincc.edu/lochbaum/11-3%20Parametric%20Equations.pdf