September 14, 2006

4th Scribe Post

Hey what's up everyone!?! , Hi I'm Tennyson today is my turn of being the scriber. Today at school we were learning more about the Quadrants,circles,and little bit of trig. There was some questions in the morning that we had to complete. Some was a bit difficult to understand but we all got through it. so here it is:

First question we had:
Which Quardrant is each angle in

Q:
1.
a). 5π/3












A:Quadrant IV

How i got the answer was that i look at my pie plate. 5 π/3 is location in the plate at 300 degrees.

b).3 π/4












A: Quadrant II

When we know that 4 π/4 is a half the circle. So if think about it 3 π/4 is not just a half yet. So you see in my graph it shows. Also 3 π/4 is in your pie plate , located at 135 degrees.

c). 23 π/4














A: Quadrant IV

well π/4 is half a circle , to make it a full cirlce it would be 8 π/4. 3 rotation around would be 24 π/4. Right now we need it to be 23 π/4, so we know that it wouldn't be just exactly 24 π/4, so we rotation it backward a little so it would be in quadrant IV. Like in my diagram.

d). -41 π/6

A: Quadrant III

Half circle would be - π/6, in order it to be full it would be -12 π/6. Goes around three times, it would equal to -48 π/6, we want it to be -41 π/6, so we go backward to equal -41. The differences between this question than the others is because of the negative , so when it rotates in a circle it goes the opposite direction.


2.
Q:Find P(θ) the coordintates of the point P on the unit circle that intersects A line drawn from the origin through the point (9,-40).


A:(9)2 +(-40)2 = r2
root of 1681
r= 41
y/-40 = 1/41 --> y= -40/41
x/9 = 1/41 -- > x= 9/41
P θ = (9/41,-40/41)

A:x2+x2 = (2)2
2(x)2/2 = 4/2
x= root 4
x=root 2

During class we were talking about , having θ is very important when it is in a sin,tan,or even cos. Like Without θ in the word sin, it would just be SIN , meaing doing something bad. So you have to have &theta right after.
Example : sinθ

The other thing we were talking about is the word "Invert".We know how to do it, but we don't know what it means.Invert is when your undoing your first answer into another answer that means the same. I know this might sound confusing here's a example:

sinθ=1/2
when you undo it, it would be:
sinθ-1 = 30 deg

How the answer is the same , is when you have:
sinθ30= 1/2
So really your going backwards.


Well i hope you enjoy my post , if it sucks, hey! it's my first time.
bye
...P.S next person is littlelisa262

2 comments:

  1. Hi Tennyson. This is a great scribe post. You explain what you need to with your images and your use of colour. I like your "just the facts"
    to the point approach to this post.

    Good Job

    Mr. Harbeck
    Sargent Park School

    ReplyDelete
  2. Hi Tennyson,

    I found it very helpful that you introduced the topics of your scribe in the first paragraph!

    Best,
    Lani

    ReplyDelete