Math songs
Below are the math songs we sang in class, hope you get to sing them to someone else!
You can see some more logic problems (with a ranking for difficulty) by following the link below.
http://www.geocities.com/Heartland/Plains/4484/logic.htm#xpls
I have a list of topics for the exam prepared. I will give you a paper copy of it tomorrow, but you can download a copy of it to start your revision tonight if you wish. I will try and give you some questions you can work on (for the topics from the 2nd semester since I have given you a list of questions for the first semester already in preparation for your midyear exams).
About 70% of the material will be questions from this semester and about 30% will be questions from first semester.
This class we learned how to solve exponential equations using logarithms. Mr Wees gave such examples:
ex1)
To solve you multiply by
on each side
To receive x on its own
Then use logarithm rule #6:
ex2)
To solve we subsituted
for y, to receive a quadratic equation
We then factor the equation
(y-3)(y-2)=0
Then resubsituted
And then solve for x which gives us
ex3) This example was solved in terms of logx and logy
We then used the logarithms rules #1 and #3
Then we applied logarithm rul #2 to remove the exponents
=4logx + 6logy - 5logx
And combined like terms for our result
=6logy - logx
The remaining time of this class we worked on a worksheet.
I nominate mikbin to make the next class entry.
xoxoxo
Check out this bouncing ball applet.
http://www.jensign.com/JavaScience/www/bounce/bounce.html
How does this resemble a geometric series?
Can you estimate the value of r for the heights of this series?
How would you find the distance the ball has travelled?
If you want some practice with arithmetic sequences, check out the link below.
http://www.interactivestuff.org/sums4fun/sequences.html
Also, for a link to many different examples of fun interactive web mathematics, check out this page.
I'm collecting some resources we can use to solve systems of equations.
Here is a tutorial that explains how to solve a system of equations using your TI graphing calculator.
Here is a resource for playing around with Gaussian elimination and trying to figure out how to make it work.
and finally, here is a resource for solving systems of equations, quadratic equations, or normal one variable equations. It also shows most of the steps involved in solving the equations.
Today, we worked on how to solve 3 simultaneous equations. Mr Wees taught us 2 ways to do it.
Firstly, the method by gaussian elimination:
ex. -(1)- 3x + 4y + 3z = 10
-(2)- 2x - 3y + 2z = 6
-(3)- 1x - 1y + 10z = 20
Now, we simplify -(1)- and -(2)- : 3 *-(1)- + 4 *-(2)- => 17x + 17z = 54
Then, we simplify -(1)- and -(3)- : 1 * -(1)- + 4*-(3)- => 7x + 43z = 90
At this point, we have 2 equations with 2 unknowns, easily solvable.
Secondly by metrics, but I think it is just useful to know how our calculators proceed (because it's much more difficult than the first one!)
Each line constitutes an equation:
-(1)- 1 2 3 | 1
-(2)- 4 2 3 | 10
-(3)- 5 1 2 | 20
We simplify each one of them separately; such as:
-(2)- - 4 * -(1)- and -(3)- - 5 * -(1)-
which gives us
-(1)- 1 2 3 | 1
-(2)- 0 -6 -9 | 6
-(3)- 0 -9 -13 | 15
Then we multiply -(2)- by -1/6:
-(1)- 1 2 3 | 1
-(2)- 0 1 1.5 | -1
-(3)- 0 -9 -13 | 15
We simplify -(2)- and -(3)- together by doing -(3)- + 9 * -(2)-, which gives:
-(1)- 1 2 3 | 1
-(2)- 0 1 1.5 | -1
-(3)- 0 0 0.5 | 6
Then we do 2 * -(3)- to find z:
-(1)- 1 2 3 | 1
-(2)- 0 1 1.5 | -1
-(3)- 0 0 1 | 12
so z = 12
At this point, we do back substitution to find x and y (by replacing z by its value in the other equations) :
y + 1.5 (12) = -1
y = -19
x + 2(-19) + 3 (12) = 1
x - 38 + 36 = 1
x = 3
And we got the 3 unknowns :)
At the end of the period, we took different points from a video showing the different places of a ball being thrown. With the coordinates of 3 points, our homework assignement is to find the equation of the function (y = ax² + bx + c) using the tools we have learnt today.
I have no idea of who didn't get the chance to write a résumé yet, so perhaps we could sort it out on Wednesday ?!
-Origny
There are some alternatives to Equation Editor you can use some of the following alternatives:
MathCast - This allows you to create equations, and then copy and paste the equations into Microsoft Word and other such applications. You can download this code from here. Make sure you extract the file you download into a new directory (otherwise you will end up with a mess of files on your desktop, which is never pretty). You then simply double click on MathCast.exe to run the file.
WebEq - You can use this program again, which comes with a 30 day evaluation version. Just download it from here.
Of course both of these options assume you are using a PC with Windows as your operating system. If you are using a Mac, you can use instead:
Actually I couldn't find any good solutions for the Mac. WebEq apparently (same download page as above) has a Mac version of their software. Your other option is to visit this page, but you will both have to download their software, and TeX for Mac OS X. You will ALSO need to use the TeX language to create the equations.
Your best bet, if you are using a Mac, is to have a window of http://www.forkosh.com/mimetex.html open, and just copy and paste the images that his Mimetex equation generator creates directly into your Word document.
Here's a place where the students of the 10th grade Extended class can summarize their lessons. They will be able to include mathematical equations in their entries using [tex] and [/tex] tags. (see the tutorial here)
As the year progresses we hope the summaries get better. What will happen is that when one student posts, they get to choose the next student. However they cannot choose someone who has already done as many posts as they have done (so that each person get picked at some point).
This is the blog for Mr. Wees' classes. Here we will be able to include images, flash files, mathematical discussions, or whatever else is relevant to our discussions.
We can also include mathematical equations in our posts, like
.
You can also see a tutorial on how to include mathematical equations here