- #1
omg precal
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First of all, sorry for asking so many questions. I do not want answers, just a method of solving them.
For the exponential function f(x) = ab^x, suppose f(2) = 2 and f(4) = 18.
a. Find a and b.
b. Find f^-1(54), the inverse function.
None, really...
a. f(2) = 2, meaning ab^2 = 2. f(4) = 18, meaning ab^4 = 18.
(ab^2 = 2) * 9 -> 9ab^2 = 18
ab^4 = 18
9ab^2 = ab^4
divide both sides by ab^2
9 = b^2
b = 3
a(3)^2 = 2
9a = 2
a = 2/9
b. The inverse of ab^54...
Inverse of: (2/9)(3)^54
And from here, I'm lost. Do you fifty-fourth root everything because it is the inverse?
Homework Statement
For the exponential function f(x) = ab^x, suppose f(2) = 2 and f(4) = 18.
a. Find a and b.
b. Find f^-1(54), the inverse function.
Homework Equations
None, really...
The Attempt at a Solution
a. f(2) = 2, meaning ab^2 = 2. f(4) = 18, meaning ab^4 = 18.
(ab^2 = 2) * 9 -> 9ab^2 = 18
ab^4 = 18
9ab^2 = ab^4
divide both sides by ab^2
9 = b^2
b = 3
a(3)^2 = 2
9a = 2
a = 2/9
b. The inverse of ab^54...
Inverse of: (2/9)(3)^54
And from here, I'm lost. Do you fifty-fourth root everything because it is the inverse?