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If f=(x) is an exponential function where f(1)=8 and f(10.5)=72 then find the value of f(3.5)

User Mapm
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1 Answer

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Answer: We know that the function f(x) is an exponential function. An exponential function can be written in the form:

f(x) = a * b^x

where:

a = the initial value (when x = 0)

b = the base of the exponential function

x = the independent variable

To find the values of a and b, we can use the given information:

f(1) = 8, so:

8 = a * b^1

8 = a * b

f(10.5) = 72, so:

72 = a * b^10.5

We can now use the first equation to solve for a:

a = 8/b

Substituting this value into the second equation, we get:

72 = (8/b) * b^10.5

Simplifying:

72 = 8 * b^9.5

9 = b^9.5

b = 9^(1/9.5)

b = 1.4608 (approx.)

Substituting the values of a and b into the exponential function, we get:

f(x) = 8 * 1.4608^x

Now we can find f(3.5):

f(3.5) = 8 * 1.4608^3.5

f(3.5) = 8 * 6.2797

f(3.5) = 50.2376 (approx.)

Therefore, f(3.5) is approximately equal to 50.24.

Explanation:

User Laquandra
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