## Wednesday, February 11, 2009

### (8) I Wanna Be, The Very Best... NOT!

Math-ew's Super Awesome Scribe Post

Hey Pre-Cal 40-S Winter 2009! This is Matthew Aka Pokemon Champion (though apparently Mr. K's son may have something to say about that... bring it Mr. K Junior... Just kidding =D)

Anywayyyyys... today we started off class with Mr. K very likely confusing or scaring our parents by implementing use of the "yackpack" tool on the blog. he first announced who we were ( We come in peace?) and then we all just sorta started to laugh, and now some of our parents are wondering why they are suddenly the stars of a latest sitcom ( My Child the Precal Student, perhaps?)

Ah, but I digress, back to the math! After our excitement died down a bit, the slideshow appeared, in all it's magical Smart Board glory. A very similar premiere slide appeared today, now with a new caption. Today we were to delve into the wonder that is solving trigonometric equations! (really this time).

We started out with some fairly simple questions reminiscent of the day before. Determine trigonometric values and come to an exact value as an answer. Here are the questions along with some straight-forward solutions.

Something Mr. K touched upon was the concept that we don't exactly NEED to rationalize the denominator anymore as far as radicals go. No matter where you put the radical, it's still there. and sometimes it's probably even more handy to eliminate radicals from the numerator and have them all on the denominator, but I used the answer where we do rationalize radicals in the denominator. Heavy stuff...

We then had a bit of a mental math jamboree! Or, just a mental math quiz, about SohCahToa/ChoShaCao of certain angles. It was out of 10 and it seemed like a big problem was the last question resulting in an answer of "undefined". Always make sure to check when you have 1/0 or 0/1 because their meanings are quite different..

Yesterday we had also started to talk about phi, or if the symbol interests you at all. Phi as a refresher, is just another fun Greek letter/symbol (huzzah for the Greeks!) meaning the related angle of "theta". Today we started investigating the use of it a little bit more.

Now we started doing questions using the inverse, or arc, trigonometric functions. For each given value, we should end up with 2 different angles (except of course, in the case of 90,180.270, and 360 degrees.) To spice things up a little bit - solving for the angles in radians. I won't bother with the first question of the type because it's basically a question we all know and love using a common sin value on the unit circle. For those who need it, the answers result in Pi/4 or 3Pi/4.

It was after this question that "Phi" came in.

Here are the 2 questions we solved using phi:
Next up, we took a look at some good old fashioned algebraic equations.These should have been easily solved, and were somewhat of a break from the slightly more difficult concepts we are trying to grip now. Checking the slide for this one should be more than enough of a refresher for everybody, but i put it here as well just in case. Our last slide for the day was almost a carbon copy of this one except now it incorporated trig functions. Now (trig function)x= 1/2 or 1/3 rather than just x. These questions are solved in the same way as with the phi questions previously shown. Rather than give you the answers here, i think it would be quite prudent for you all to just try to figure the last slide out combining our knowledge from slides 4 and 5 with slide 6 and seeing what you can do as far as that goes.

Last bits of info! Today Mr. K taught us a handy trick to do with our TI-83/84 calculators ( as well as revealing the secret of the almighty TI-89, but let's not get too excited). After you have some sort of number you want stored into memory, you can press the STO key, then the GREEN ALPHA KEY followed by a letter of your choice (although X is NOT advised due to its use in other areas in the calcualtor). He then went on to tell us that our entire calculators will be wiped before the exam and that, not even our fun puzzle games would survive... tear tear :(
Homework for tonight was Exercise 4 Q's 1-10, and any 5 of the last 10.
It was also suggested that we draw unit circles and to use lots of colour. He mentioned how important colour is and how it can help us remember things, such as how we recognize yellow early on but not to rely on it because its a very bright and hard to read colour. Anyways sorry for the lateness.... REALLY lateness... Computer kept freezing up and had no notes so kind of had to wing it.. But excuses are lame and i'll try to manage my time better next time. Hopefully This helped some people out... it wasn't as awesome as I intended it to be but what can ya do?
NEXT SCRIBE ISSSSSS: *unnecessary drum roll* REBECCA!!! Congratz!! XD Good night every one, and happy mathing! =D