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1960’s Arithmetic test:

“A logger cuts and sells a truck load of lumber for $100. His cost of production is four-fiths of that amount.
What is his profit?”

70’s New Math test:

“A logger exchanges a set (L) of lumber for a set (M) of money. The cardinality of set M is 100. The set C of production costs contains 20 fewer points.
What is the cardinality of set P of profits?”

80’s education reform version:

“A logger cuts and sells a truckload of lumber for $100. His cost is $80, and his profit is $20.
Find and circle the number 20.”

90’s version:

“An unenlightened logger cuts down a beautiful stand of 100 old growth trees in order to make a $20 profit.
Write an essay explaining how you feel about this as a way of making money.
Topic for discussion: How did the forest birds and squirrels feel?”

Snijpunten van wortel functies en rechte lijnen en van twee wortelfuncties

a) √(8-2X) = X

8-2X = X^2
X^2+2x-8 = 0
(X-2)(X+4)
X = 2 v X = -4
X = -4 voldoet niet; deze oplossing is ingevoerd door het kwadrateren.
Invullen geeft coördinaat snijpunt: (2,2).

b) √(3-X) = √X
3-X = X
2X = 3
X = 3/2

c) 3-X = √(3X+1)
9-6X+X^2 = 3X+1
X^2-9X+8 = 0
(X-1)(X-8)
X = 1 v X = 8
X = 8 voldoet niet; deze oplossing is ingevoerd door het kwadrateren.
Invullen geeft coördinaat snijpunt: (1,2).