SOLUTION: What is the inverse of: f(x)=3x^3+8

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Question 1087242: What is the inverse of: f(x)=3x^3+8
Found 2 solutions by MathLover1, rothauserc:
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

the inverse of:
f%28x%29=3x%5E3%2B8......since f%28x%29=y we have
y=3x%5E3%2B8.....swap x and y
x=3y%5E3%2B8....sole for y
x-8=3y%5E3
%28x-8%29%2F3=y%5E3
y=root%283%2C%28x-8%29%2F3%29
f%5E-1%28x%29=root%283%2C%28x-8%29%2F3%29

Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
f(x) = 3x^3 +8
:
y = 3x^3 +8
:
x = 3y^3 +8
:
3y^3 = x -8
:
y^3 = (x -8) / 3
:
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f^(-1) (x) = ((x -8) / 3)^(1/3)
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