SOLUTION: How would you find the logarithmic or exponential equation of the graph, when one of the points is (4,1) and the other is at (1,0)? Thanks!

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Question 70879: How would you find the logarithmic or exponential equation of the graph, when one of the points is (4,1) and the other is at (1,0)?
Thanks!

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
How would you find the logarithmic or exponential equation of the graph, when one of the points is (4,1) and the other is at (1,0)?
:
This looks like a logarithmic function (x increases much faster than y)
:
It's easier to find the exponential function which is the inverse of this
Reverse the x,y values: 1,4 and 0,1
:
y = b^x
4 = b^1
b = 4
:
Check it using coordinates 0,1
y = 4^0
y = 1
:
the inverse of of an exponential function:
y = logb(x) and is the logarithmic function
:
y = log(base 4)(x)
x = 4^y
4 = 4^1
and
1 = 4^0