Precal Blog

Hey Everyone, I was just looking on the internet and found this pretty cool site.

If you are having trouble with transformations of sinusoids this is a good site for you.

http://mathdemos.gcsu.edu/mathdemos/sinusoidapp/sinusoidpractice.html

Hello all.  Ok, so I know that this advice might sound really lame because it involves the book, but… here goes.

Depending on what you need to study and for what learning targets, the textbook has some excellent tables that sum up key points in some of the sections.  There are the following tables in sections that we have covered up till this point in time:

Restricted Domain and Boolean Variables on pg 12, Dilations and Translations on pg 19, Composite Function on pg 25, Function Inverses on pg 32, Reflections Across the Coordinate Axes on pg 36, Absolute Value Transformations on pg 37, Even Function and Odd Function on pg 38, Standard Position of an Angle on pg 54, Coterminal Angles on pg 55, Reference Angle on pg 55, Periodic Function on pg 59, Sine and Cosine Functions of Any Size Angle on pg 60, The Six Trigonometric Functions on pg 65, Inverse Trigonometric Functions on pg 71, General Sinusoidal Equation on pg 86, & Period and Frequency of a Sinusoid on pg 87. 

I know it seems like a lot now, but look through the titles for specific things you might need help on.  Also, because even and odd functions and inverse functions seem to be very popular on our blog, look at Mr Bieniek’s comments or at pgs 37-38 and section 1.5.

Also, just to clear the air about the Quarter Journals, they’re really simple.  You know that you need small reflection in the form of an essay-ish thingy on the quarter, anything you posted here, and your yellow sheets.  According to Mr Bieniek, you need 10 yellow sheets total: sections 1.1-1.6, 2.2-2.4, and 3.2.

Well, that’s all for now.  Make sure you study, but don’t freak out Look through the list of LTs (#s 10-18) and focus on what you aren’t so sure of.  If you have questions, POST!!!  If you have answers, POST!!!  Good luck!

Lindsay

Well 3rd hour didn’t exactly come up with any questions about the assignment but i have a few questions of my own that i feel everybody else would like answered as well. 

Okay 1. For our quarter journals,i know the 3 parts we have to include: The chapter reviews, the blog entries, and our reflection.  I also recall you saying to add something extra if you want it to be an “A”.  Is there anything in particular that you wanted or just come up with something creative on our own.  (Which is my guess what it is)

 2.  I dont exactly remember even and odd functions– i was reading over the questions from 5th hour and that was the one that really stood out to me. 

3.  Another question that stood out to me was the difference between reciprocal and inverse – can they sometimes be the same or are they always different? 

So those are just the questions and i had for you… If anybody from 3rd hour has any other questions feel free to add them!! Or an answer to mine?!?! You know i would love you forever!

First of all, the blog is up and running, but you probably know that if you’re reading this. If you weren’t here on Thursday or Friday, we’ve been reviewing for our Unit 3 Test which wil be on Tuesday . This will be the last test to go on 1st quarter so make sure you study hard! Also, since the end of the quarter is coming up, quarter journals need to be turned in by the end of the quarter.

Quarter Journals

Since I figured everyone forgot about them I’ll just post what you need for them.

Part 1.) Reading Guides: The reading guides are the yellow sheets for each of the chapters we covered. Make sure you check to see if you have all of them, and if you don’t you better start finishing them.

Part 2.) Blog Entries: All you need to do for this is print off everything you’ve posted/commented on the blog. That should be fairly simple, but don’t forget because it’s 1/3 of your journal.

Part 3.) Quarter Entries: This is basically a reflection of how you felt about the quarter. Write about what you did well/bad on this 1st quarter and include how you could do better next quarter.  Also you could add any ideas for how the blog/class could work better for the class. You may also include questions in your journal.

Monday’s scribe will be Connor

How can you tell if a graph is either sine or cosine? Well, one way to tell is if the line that is graphed goes through the origin, point (0,0) if it does then its a sine graph because the sine of 0 is 0. Though the best way to tell is by looking at where a period of the graph starts. If it goes down then its a cosine graph because a cosine graph without any transformations, always start at point (0,1). Since one is the highest value you can get if you take the cosine of a number, the y-value will go down. Sine graphs go up because the lowest value you can get if you take the sine of a number is zero. So a sine graph without any transformations will always start at (0,0). So there you have it. Sine graphs go up from a starting point, Cosine graphs go down from a starting point.

1.  Explain the difference between inverse and reciprical.

2.  How do you build an inverse function graphically, numerically, and algebraically?

3.  What are odd and even functions?

4.  What are invertible and one-to-one functions?

No one in third hour has posted in a long time, so I figured I’d pick things up. Today we refined our ability to transform sinusoidal graphs based on equations and write equations of sinusoidal graphs. In class, we worked on an exploration sheet for practice. It’s all basically review of transformations from chapter 1, but with sine and cosine functions, which differ in that sine graphs start out at the origin and cosine graphs start at `y=1` (with variation according to how they’re translated and dilated).

Tomorrow’s (or whenever’s…) scribe will be Curtis.

Okay, so, I’m going to be scribe today, because no one else has for a while, and I don’t think one was assigned…

Anyways, today we learned a lot of new stuff.  Here are a few definitions from the packet we received and my elaboration on them. 

amplitude-“the distance from the sinusoidal axis to the maximum or minimum points.”  It is the absolute value of A in the standard equation `f(x)=C+AsinBtheta` It’s the absolute value because distance, which is essentially what amplitude is, must be positive.  It can also be thought of as a vertical dilation.

sinusoidal axis- “the midline of a sine or cosine graph.”  Its C in the standard equation mentioned in the first definition.

critical points- “the maximum/minimum points.”  These points are “critical” because they are important to know when graphing an equation.

periodic function- “a function that gives the same output for inputs that are a fixed distance apart.”  In a periodic function equation, a period is `360/B` if you follow the standard equation from before.

frequency- the only definition we were given in class was that “it is the reciprocal of period.”  The rest of the packet was homework for tomorrow.

We also discussed how a sine/cosine graph’s opposite is the original sine/cosine graph’s reflection.  Not much else comes to mind for me right now.  We worked up until the bell, basically.  The test will either be Friday, Monday, or Tuesday.  That’s it I believe.  The next scribe will be…David S.

These notes are from last week, but they’re exactly what was on the SmartBoard just in case someone missed some diagrams and bullet points. These notes explain the basics of angles that are used to measure rotations. They also go over coterminal angles and reference angles.

However, one thing that we touched base on today was determining reference angles and the number of rotations on the graph. Sam’s presentation of one of the claims was especially helpful because she went through it step by step. There’s two ways to do it, and both are shown above. Thank you Sam for your excellent explanations.