Her birthday took place on a Saturday. :)
Area as a function of length can be written as
f(l) = l^2
And volume of cube can be expressed as a function of side s as,
f(s) = s^3
Problem 1
Domain = {-1, -3, 2, 1}
Range = {5, 0, 2}
The domain is the set of possible inputs and the range is the set of possible outputs. This is a function because each input goes to exactly one output.
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Problem 2
This is a function as well. We do not have any input going to multiple outputs.
Domain = {-2, -3, 5}
Range = {6, 7, 8}
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Problem 3
This is not a function. The input -4 goes to more than one output (outputs 3 and -1 at the same time)
Domain = {-4, -2, 0}
Range = {3, -1, -2, 4}
