November 21, 2006

Hey everyone, I'll be scribing for both today and yesterday's class.

Yesterday we had a what seemed like a shorter class, because Mr. K had to leave early.

In the beginning of class Mr. K talked about a new project we should start on. Which involves our favorite number, and why it's so special.

* Dont forget to sign up to flickr.com so we can post up our pictures to the tag PC30SF06

We had a review sheet that day on "Quadratic & Rational Inequalities"

Some of us had a hard time solving the questions, so Sam found our good friend Mr.Clark. He came and helped us with question 1 (h).

2x2 -7x +3 >= 0
(2x-1)(x-3) >= 0
e.p. (3,1/2)




Solution
(-oo, 1/2] U [3, oo)



He also did another example


(x+2) (x-1) / x+3 <= 0
e.p. (-2,1,-3) Nothing else really happened in that class so we continued to work on our review sheet.

~~~~~~~

Today's class we worked on the question Mr K gave us.
Which were: Slove

1. a) x2+3x >= 18
b) 2x+5/x+1 <= x+1/x-1
c) |3-4x| > 9

d) |5x-8| <= 2

2. There are $950 in $5, $10, and $20 bills in the cash regester. There are a total of 71 bills. The number of $20 bills is 7 less than the total number of $5 and $10 bills. How many bills of each denomination are in the cash regester.

We had time to work on them and corrected it with the class.

a) x2+3x >= 18
x=3x-18 >= 0
(x-3)(x+6) >= 0


Solution
(-oo,-6] U [3,oo)


b)
2x+5/x+1 <= x+1/x-1
x can not = -1 , 1
we multiply each side by (x+1) (x-1) then we'll get.

2x2 + 3x-5 <= x2+2x +1

x2 + x -6 <= 0 (x+3) (x+2) <= 0

Solution
[-3, -1) U (-1, 1) U (1, 2]

c) |3-4x| > 9



d) |5x-8| <= 2


2) # 5 bills = F
# 10 bills = N
# 20 bills = W

equations
F+ N+ W = 71
5F + 10N + 20W = 925
-F - N + W = -7





There are 21 $5 bills, 18 $10 bills and 32 $20 bills.

Don't forget our pre test is tomorrow and our test for this unit will be on Monday.

Tomorrows scribe isss........ Crysta!! have fun!!

** Don't forget to do the review down there\/

1 comment:

  1. :)
    i like this scribe...cuz u did the L1 L2 stuff as an image...which is neat!

    ReplyDelete