## Tuesday, March 25, 2008

### BOB Version 3: Trigonometric Identities

I found this unit less daunting than the other previous units we've done so far. (This is because we don't have to memorize something huge that's like worth 1 megabyte of our memory, such as the unit circle, or get anxious over a graphing portion of a unit--because there is no graphing portion in this unit.) Comparing topics in this unit, I liked the "prove the following identity" part because it seems to be the easiest topic to absorb. Remembering how to do the sine dance (which aided us in remembering how to remember the 'dancing equations'--that's what I call them) helped out A LOT, and so, I found doing those questions without difficulty.

As of now, I have to go over the slides for the proofs of sum and differences because I haven't yet looked at them! I'm not too comfortable with questions where the questions tell what alpha and beta are, then we would have to draw a circle to find out quadrants they're in, then use the dancing equations to determine where a point is in which quadrant--because right now I'm having trouble wrapping my head around the 'setting up' part where we have to draw the circle to see what angle alpha, beta, a, or b are in. If you don't know what I'm talking about, then refer to March 20's slide #4 and 5, please and thank you! But now, I've just recently had a moment of clarity and doing those kinds of questions make sense to me.

Also, one of the questions in our homework that was assigned, EXERCISE 16: SUM AND DIFFERENCE IDENTITIES I, #9, it tells us to graph sin (t + 3pi/2) = -cos t, in which I have no idea how to graph that. And there maybe more questions that I'm not comfortable in doing because I haven't looked at them yet.

The test on trig. identities is set for Friday, and I'm sure I can prepare myself before that day. So 'til then, may we all grok in fullness!

P.S. Is it just me or did Mr.K not posted up today's slides? I was planning on using those slides to study off of because I was going to look over those slides thinking it would be more convenient for me to study off of since I am on the computer now typing up my blog post.