Wednesday, September 30, 2009
Friday, September 25, 2009
Thursday, September 24, 2009
Monday, September 21, 2009
Hello All - I've read your reflection posts, and your concerns are all over the place. Some people are most concerned about direct and inverse variation, others about solving absolute value inequalities, others graphing.
As part of your studying, remember to check out the absvalue label on this blog. It will show you all the class notes and the scribe posts from the unit.
Sunday, September 20, 2009
Saturday, September 19, 2009
Friday, September 18, 2009
Thursday, September 17, 2009
We then moved onto page 6 of our pink packet and took some notes.
- Standard Absolute Value Form: y = a [ x - h ] + k
- (h,k) represent the cordinates of the vertex of the graph
Each variable has an effect on the graph.
h - translation right or left
- y = [ x + 4 ] makes the vertex of the graph 4 to the left on the X-axis
- y = [ x - 3 ] makes the vertext of the graph 3 to the right on the X-axis
- *Be careful! Positive means to the left, negative to the right! Opposite of what we're used to!
k - translation up or down
- y = [ x ] + 4 makes the vertex 4 up on the Y-axis
- y = [ x ] - 3 makes the vertex 3 down on the Y-axis
a - (the multiplyer) controls the width of the graph and the direction in which it opens
- if a is greater than 1, it makes a narrow graph
- if a is less than 1, it will be a wide graph
- if a is positive the graph will open upward
- if a is negative the graph will open downward
*Brackets ( [ ] ) stand for the absolute value symbol. I tried using the one above the enter key but everytime I went to publish the post, they would disappear.
For Example if you have y=l x+3 l then you would move 3 to the left on your graph
if you have y=l x-2 l then you would move 2 to the right on your graph
The Y value is much less complicated and is not within the absolut value bars. You can just look at the number being added or subtracted OUTSIDE THE BARS
For example if you have y=l x l +3 then you would move 3 up on your graph (0,3)
if you have y=l x l -2 then you would move down 2 on your graph (0,-2)
These will also be in the same equation
y=l x + 4 l -2
the vertex here would be (-4, -2)
There will also be numbers being multiplied by the absolute value equation. This determines the slopes of the lines that meet at the vertex. The lines have the same slope except for they are negative. When the number is Higher (such as 5) the V will appear more narrow. When the number is smaller (such as 1/2) the V will appear wider. If the number is negative then the V is upside-down.
For Example If you have y= 3l x l then you will have the line on the right's slope as 3/1 (the line on the left will just be -3) and it will be opening up with the vertex at (0,0)
if you have y= -1/4l x l -2 then you will move down 2 on the y axis and the line on the right's slope will be -1/4 (the line on the left will be 1/4) and will be opening down with the vertex at (0,-2)
Check the Class notes to see graphs!!!
Today we worked to synthesize the STANDARD ABSOLUTE VALUE FORM
y= a l x - h l + k CHECK THE NOTES
The notes will explain it from here on out, but if you have any questions, that sucks because my scribe is complete
Tuesday, September 15, 2009
First, start solving as if it were a normal absolute value problem.
When you get your two answers you plot them on a number line. If the sign in your problem is a "less/greater than or equal to" you shade in your plotted points. If it is just a "less/greater than" sign you leave the circle open, or unshaded. These plotted points are called "critical points".
Then you pick three numbers to test in the original equation. One number must be lesser than the lower critical point, one greater than the higher point and one that's between the two points. If a test point works, you shade from one of your critical points toward the point and all numbers included in that shading answer the inequality.
Answers are written with the "x"being compared to the two critical points using inequality signs. Here are examples: 6 < x < 9
I don't really see the point in me posting this since all the notes are already on the blog, but here it is anyway.
Monday, September 14, 2009
Sunday, September 13, 2009
Saturday, September 12, 2009
When you login you should see that the Pre-course diagnostic test has been assigned. Complete this by Monday.
You'll want to have scratch paper, a pencil, and a calculator available.
You can press the Stop Test button (it's red) to save and continue later, if you can't finish it all at once.