SOLUTION: Find a possible formula for a power function with the properties that f(1)=3/2 and f(2)=3/8. You must show calculations justifying your formula. Help me please?

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Question 981783: Find a possible formula for a power function with the properties that f(1)=3/2 and f(2)=3/8. You must show calculations justifying your formula.
Help me please?

Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
Instead of doing your problem, I will do one EXACTLY in every detail like
your problem.  Then you can use it as a model to do yours by:

I will do this one:

Find a possible formula for a power function with the properties that
g(3)=4/3 and g(4)=4/9.
I start by assuming the general power formula for g(x)

g%28x%29%22%22=%22%22A%2AB%5Ex

I substitute x=3 and set that equal to 4/3:

g%283%29%22%22=%22%22A%2AB%5E3%22%22=%22%224%2F3

Then I substitute x=4 and set that equal to 4/9:

g%284%29%22%22=%22%22A%2AB%5E4%22%22=%22%224%2F9

Then I divide equals by equals dividing g(4) by g(3)

%22g%284%29%22%2F%22g%283%29%22%22%22=%22%22%28A%2AB%5E4%29%2F%28A%2AB%5E3%29%22%22=%22%22%284%2F9%29%2F%284%2F3%29

        %28cross%28A%29%2AB%5Ecross%284%29%29%2F%28cross%28A%29%2Across%28B%5E3%29%29%22%22=%22%2212%2F36

        B%22%22=%22%221%2F3

I substitute that in A%2AB%5E3%22%22=%22%224%2F3

              A%2A%281%2F3%29%5E3%22%22=%22%224%2F3

              A%2A%281%2F27%29%22%22=%22%224%2F3

I multiply both sides by 27 to clear of fractions:

              A%22%22=%22%2227%2Aexpr%284%2F3%29

              A%22=%22%2236

Therefore my power function g%28x%29%22%22=%22%22A%2AB%5Ex becomes
              
Answer:       g%28x%29%22%22=%22%2236%2A%281%2F3%29%5Ex

Now do your problem exactly the same way I did mine.

Edwin