Royce is folding a piece of paper to make an origami figure. Each time he folds the paper, the thickness of the paper is doubled. The paper starts out flat, with a thickness of 2 millimeters. A. Write a list of six ordered pairs showing the output as the thickness of the paper when the input is the number of times it is folded. Explain how you came up with your ordered pairs. B. Is this relation a function? Explain why or why not using the ordered pairs you came up with in Part A.
i already did A
The ordered pairs in the first part will be in the form (x,y) = (#folds, Thickness) The initial condition when x = #folds = 0 ; is y = thickness = 2 mm
number of folds thickness 0 2 1 4 2 6 3 8 4 10 5 12
Do you think this is a function?
yes
each value is 2 times the last value, exponential
ooh
your points are a little off, they are 2,4,8,16,32,64......
oh, so 2,4 8,16 etc
so it's double
number of folds thickness (0,2) (1,4) (2,8) (3,16) (4,32) (5,64) . . .
The general form for this type of function is \[y(x) = A*b^x\] have you seen that before?
ive seen those type of things with numbers
Put in the first point where x=0 and y=2, that will give you the value for the A . \[y(0) =2= A*b^0 \]
b to the zero power = 1, so 2 = A*1 ... A = 2
uh do i mulitiply 0 x 2
what
Now you know, \[y(x) = 2 *b^x\] Now use another point , and figure out what b is
The second point is (x,y) = (1 , 4) \[y(1)=4 = 2*b^1\]
8?
\[b^1=2\] b=2 The overall function becomes,
\[y(x) = 2*2^x\]
ohhh
It is a function because for all the elements in its domain, (All x values greater than or equal to zero), there is one value in the range, (all y values greater than or equal to 2)
What does your book give as the definition for a function?
its not a book @DanJS
It is a function because each input x, gives one output, y
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