Question 82533
x -2 -1 0 1 2
y .25 .5 1 2 4
Given the table above, graph the function, identify the graph of the function (line, parabola, hyperbola, or exponential), explain your choice,
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Looking at the changes in y for each value of x, it look like an exponential
y = a^x, find a using the 1st coordinates; -2,.25
:
.25 = a^-2 
.25 = {{{1/a^2}}}
.25a^2 = 1
a^2 = 1/.25
a^2 = 4
a = 2
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Our exponential equation is y = 2^x, checks reveal for each value of x we
get the value of y as given in the table.
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For example using x = 2
y = 2^2
y = 4 as given 
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give the domain and range as shown in the graph,
drawing a graph from this:
{{{ graph( 300, 200, -6, 6, -2, 6, 2^x) }}}
Note that it approaches y = 0 but never reaches it
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and also the domain and range of the entire function.
The domain: x |x| all real numbers
The range: y |y| all numbers > 0
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