Jan. 28 scribe post

We started class by going over the homework which was the Francois and his Pendometer sheet. We went over question #2 which was the first graph. We learned that it was periotic, which is how long it takes to repeat, in this case it was 8 units. There didn't seem to be a lot of questions from the class on these first graphs. Next, we went over #6 c and looked at x(1362). To do this you divide: 1362/8 then find the remainder. The next problem was #9, and here there seemed to be more problems for the class. I didn't fully understand this problem. I think the k as a variable threw me at first. I didn't realize that you must take the smallest non negative number and then add k. Many people did this in different ways such as writing it in sequent notation. Mr. O'Brien said it was fine because it was a homework, but from now on we should write it as set notation, which we will learn more later on in the unit. Next on the list was #11, and we learned that it could be and infinate amount of answers. Dan asked a question about k∈Z. And, the answer was that Z is the set of integars, and ∈ is the element. When I was doing this homework I to was confused on what this meant by this, but after this discussion I know what is meant by it. We skipped down to to the last page because there weren't any questions , and the last page is where it got more complicated. π/4 is half of π/2, using this and drawing a 45,45,90 triangle in the circle to find what 1/8 of the circle is and it will make it easier to solve question #17. Next we learned what FuFOO is which is funny form of 1. Did all you guys understand all this on the last page before today's discussion? because I know that I didn't. For question 18 there was problems as well. Again we took the circle and divided it into fourths, then drew a 30,60, 90 into the circle, and found out the length of the sides my looking at the ratios.
Fraction of Circumference:
30/360 * 2π
1/12 * 2π
π/6

For # 21 and 22 Mr. O'brien said to hold off on them.

Next we took out our laptops and used Geogebra, and he handed out a packet of notes labeled Introduction to Trigonometry Notes . These will be all of our notes for the next couple of days. People may want to look over these and make sure that they are comfortable with all of this information.

Using Geogebra: We first made an angle using a ray. We can't use a line because a line goes on forever. Therefore use a couple rays to make an angle. Select the one point, then the vertex, then the other point to measure the angle. To change the angle click on a point and drag it to change the measurement of it. When measuring one ray is called the initial and the other is the terminal. It is always measured from initial to the terminal. It is possible to go past 360 degrees for an angle. We learned that we can't break sin. Its domain is all real numbers. Standard position is what we next learned but I don't think I fully really understand what this is... I think you measure from right to left.

Radian Definition: θ = arc length/ radius

To make an arc we first select the center then the point on one ray, then the point on the other ray. This is after going up into the tool bar and finding the right selection to make arcs.

180 degrees = π rads which works out with Francois. 90 degrees = π/2. These answers were our answers in the Francois problems as well.

On the blog there are two links under the homework for next class that would be good to look at. The first shows a circle with points that you can quiz yourself on. Also there is a link to quizlet for flashcards.

Collin is the scribe for next class.