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Write a power function (y=ax^b) whose graph passes through the points (2,5) and (6,9)

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Answer:

To find the values of a and b that make the power function y = ax^b pass through the points (2,5) and (6,9), we can use the following system of equations:

5 = a2^b

9 = a6^b

We need to solve for a and b in this system.

One way to do this is to divide the second equation by the first equation, which eliminates a and gives:

9/5 = (6/2)^b

Simplifying this gives:

9/5 = 3^b

Taking the logarithm of both sides (with any base) gives:

log(9/5) = log(3^b)

Using the logarithmic property that log(a^b) = b*log(a), we get:

log(9/5) = b*log(3)

Solving for b, we get:

b = log(9/5) / log(3)

Plugging this value of b into one of the original equations (e.g., the first one) gives:

5 = a*2^(log(9/5)/log(3))

Solving for a, we get:

a = 5 / 2^(log(9/5)/log(3))

User Sten Roger Sandvik
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