Today's Slides: June 12

Here they are ...





To see a larger image of the slides go here. When you get there you'll see a button in the bottom right-hand corner that says [full]. Click it and the slides will display in full screen mode.

BOB

We're at the end of another unit again! This unit was okay. At the beginning it was pretty easy to understand... until we applied what we learned into word problems. Some word problems are easier than others, but I always have a problem approaching the problem and not knowing what I need to look for. I think all I really need to do is read the problem very carefully and idenitify what is given to me and what I need to solve. Bu overall, I guess this unit was quite easy and quick. I just hope I do good on the test!!!

BoB, Ivy

Well.. my bob is late.....umm... periodic functions...is not really fun for me...but my understanding to this unit is 75% out of a 100 %. Some questions is pretty to understand..but some are not... let just say some of the vocabulary use in some questions is not in my level..hahaha..well i will try to understand it...i think i just need to break the questions in parts to understand it...with DABC...Well...wish you all luck..and i will my self too....

BOB

OMG, i can't believe that this is like the second last unit we are learning, whoa. Well anyways my thought about this unit is that it is a simple when you really understand what you are looking for. I think that the test is going to be kinda hard just becuase, the unit was rushed. I think that if their was a few more days and a few more expamples i would do fine, but the year is coming to an end and we still have 1 more unit to do. Periodic function is kinda easy just rememeber DABC.

Periodic Functions

Whoa!! I almost forgot I was the scribe for today. Anyways...here it is..In class , we worked on a periodic function problem as groups of 3 or 4. It took us a while to figure out this problem so we had spies from each group to see what the other groups had done. Here is a recap on the problem.

A tsunami(commonly called a "tidal wave" because its effect is rapid change in tide) is a fast-moving ocean wave caused by an underwater earthquake. The water first goes down form its normal level, then rises an equal distance above its normal level, and finally return ti its normal level. The period is about 15 minutes. Suppose that a tsunami with an amplitude of 10 metres approaches the pier at Honolulu, where the normal depth of the water is 9 metres.

For this problem we first need to construct a graph and fill in "DABC".

This is how we start our graph. It stated that the normal depth of the water if 9 metres therefore it is the average value of function(sinusoidal axis). It is where our graph will start. We then add 10 metres to the sinusoidal axis since the amplitude is 10. It tell us how far to go from the sinusoidal axis. This will give us the maximum(19 metres). We then find the minimum by subtracting 10 from 9(-1).



We can now construct the graph.

The graph first goes down since it is stated in the information that the water first goes down from its normal depth. This wave has an amplitude of 10(as stated earlier) therefore the wave goes down its minimum depth which is -1. It also says that it then goes back to its normal depth at the same equal time. Therefore we divide the whole period(which is 15 ) into 4 parts because it first goes down then up, then up again and finally down.

We can now find "DABC"

A= -10 ( amplitude. it is negative because the first movement of the wave is down)

B=2(pi)/15 ( determines the period , we place 15 because a period is every 15 mins)

C=0 (since the wave started at 0 minutes and at the sinusoidal axis, there is no horizontal shift)

D= 9 ( this tells us that the whole graph will move 9 metres up, it is the sinusoidal axis)

Now we can put these informations into an equation.


The amplitude
2 Pi(3.14) / 15 = o.42
The vertical shift\

A) Assuming that the depth of the wave varies sinusoidally with time as the tsunami passes, predict the depth of the water at the following times after the tsunami first reaches the pier.

i) 2 minutes ii) 4 minutes iii) 12 minutes

For this problem, we could just insert these times into the equation in place of x to determine the depth of the water. For example, this is the equation for 2 minutes:

We do the same for the rest, place the minutes in place of x.

B) According to your model, what will be the minimum depth of the water? How do you interpret this answer in terms of what will happen in the real world?

We can see the lowest depth of the water by looking at our graph. It is -1 since it is the lowest the wave can go. In the real world this is kind of confusing. How can the lowest depth be -1 , this would mean it digs under see bottom. Therefore we state it as , for lenght of time the wave is at its lowest, we can see the bottom.

C) The wavelenght of the water is the distance a crest of the wave travels in one period. It is also equal to the distance between two adjacent crests. If a tsunami travels at 800 kilometers per hour, what is the wavelenght?

For this question. it is stated that the the wave is traveling 800 km/h. In our graph, one period of the wave is 15 minutes. We found the answer for this question by cross multiply.

THE NEXT SCRIBE IS CHRIS A.!!!!

BOB

This unit was ok, just got to redo some of the questions to remeber.It was easy to to learn.sorry but i perfer personal finance lol , i just love it. I think this is easier than pre-cal ,cuz in precal u had to know sine and cos function but for applied it just sine. so yeha. good luck eveyrone. by3

BOB

...Well our unit of Periodic Functions is done, to me it went by extremely fast. It actually was a pretty short unit. I don't know I guess it was ok, but not my favorite. I missed a day of school which just happened to be a double class day which sucked, because when I came back we had one class and then the pretest. I'm not really comfortable with the material, which sucks but I guess I know the basics I like making the equations and I understand the basic graph stuff and mon, max and intersection etc. Hopefully everything comes together and all goes well. Good luck
-Britt<3

BOB

Periodic functions was interesting.... Just when you think you have it, it hides in the back of your mind. Maybe that doesn't happen to you, but it does to me. ahahaha. This is going to be a tricky test for me. I get it, I've even participated in class withit, and the homework, but when it comes to talking about it after a nice long sleep, or if we get a break in between, it goes away. I hope i do well on the test though. Just look over the examples, and Jenn's really awesome slide, hehe. and. Bring my lucky rabbits foot, 'but not a real one, that is cruel!'

Good luck on the test!

B o B

What I think about our unit Periodic Functions is that it's not so difficult compared to Probability and Statistics. I think that "DABC" is really important to remember on answering questions on this unit. We always have to start at D, or else we might get lost. The group works helped improve my understanding about periodic functions and I think I'm ready to take the test tomorrow.
Good Luck to everyone... ~(_8^(])

BOB

The unit that we just finished about periodic functions is not that hard. We just have to read the questions carefully and understand what each value in the situation means. Just remember the word "DABC", like what Mr. K. said to help us remember. Mr. K. mentioned that quadratic equations are used in the real world, for example in tides, temparature, etc. which I found interesting. I think i am understanding the unit pretty well, and I hope I'll do good in the test tomorrow. =)

Today's Slides: May 29

Here they are ...





To see a larger image of the slides go here. When you get there you'll see a button in the bottom right-hand corner that says [full]. Click it and the slides will display in full screen mode.

B.O.B

Its that time of the month again. Im pretty sure our class has a good understanding of this unit on Periodic functions. This unit was pretty easy I guess. Its just a matter of knowing which goes where and the word that helps us in "DABC"(dabic). Wait a moment, was'nt Mr K asking us if we were ready for this test. I never got the chance to ask if our test is really tomorow....Anyways good luck!!

BOB

The periodic test is tommorow and i think im ready for it. This unit is the 2nd easiest unit, matrices being 1st. This unit was not too hard and not too easy to understand and learn. I dont think i would forget the word "DBAC" during the test since i think its a funny word, so that wont be a worry. Well anyways.. lets pass this test shall we?? =)

BOB

Soo our periodic test is tomorrow! This units okay. It's hard and easy at the same time. I think this unit is the easiest out of all the units we did. anyway i hope i pass this test! =\ heheh.

Today's Slides: May 28

The slides from our afternoon class, the pre-test, were unfortunately lost due to human error (mine -- sorry) at the end of the day.

Here the are the others ...





To see a larger image of the slides go here. When you get there you'll see a button in the bottom right-hand corner that says [full]. Click it and the slides will display in full screen mode.

May 28

Today was a double period:


First period we reviewed for our test by doing some problems in groups. Question 1 as shown in the slides introduced some words that i have never heard of. First of all there were the words Perigee and Apogree;


Perigee means the closest point to something.
Apogree means the furthest point from something.

The equation given to answer the first question was

The first question asked "How does it take for the spaceship to go around the earth."

- To answer this you are trying to find the period or (B)

- The next question was "What are the distances at the Perigree and the Apogree?"

To find the distance for the Perigree you take D-A or 550-450 = 100

To find the distance for the Apogree you take D+A or 550+450 = 1000

Question 2 is explained in the slides posted from today.

Period 2

We did our per-test.

The test is on Wednesday people and we start our final unit tomorrow.

The next scribe is Jowell.

Scribe, May 23,24 and 25

Hello everyone sorry I forgot I was scribe I know bad, this will be the scribe for Wednesday, May 23, Thursday May24 and Friday May 25.

On May 23 and 24 we got two booklets in which we were supposed to work on independently for a new unit of Design and measurement. Basically the whole unit was summarized in these two booklets but Mr.K wasn't there and we had kind of a hard time recalling this methods because it's been so long.

On Friday, when Mr K came back there was really no talk about the unit we had done while he was away. He started off by reviewing what we had done so far in periodic functions ( the slides from the past classes) and reminded us that our exam was only about 19 days away.
In slide 1 we looked at putting all the information we had done so far to a problem.


Sorry I'll finish up later my pictures don't want to work

The next scribe Is........I think were starting a new cycle

Today's Slides: May 25

Here they are ...





To see a larger image of the slides go here. When you get there you'll see a button in the bottom right-hand corner that says [full]. Click it and the slides will display in full screen mode.

MY scribe POST
may22/07



NExt person is Britt!!!!

Today's Slides: May 22

Here they are ...





To see a larger image of the slides go here. When you get there you'll see a button in the bottom right-hand corner that says [full]. Click it and the slides will display in full screen mode.