SOLUTION: Find f^-1(x) if f(x)= 3(^5√8x-9)

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Question 644844: Find f^-1(x) if f(x)= 3(^5√8x-9)
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
in case you have this:
f%28x%29=+3%285sqrt%288x%29-9%29
Solution:
1.
y=+3%285sqrt%288x%29-9%29
2.
x=+3%285sqrt%288y%29-9%29
x=+15sqrt%288y%29-27
3.
15sqrt%288y%29=x%2B27
sqrt%288y%29=%28x%2B27%29%2F15
8y=%28%28x%2B27%29%2F15%29%5E2
y=%28%28x%2B27%29%2F15%29%5E2%2F8
y=%28%28x%5E2%2B54x%2B729%29%2F225%29%2F8

y=%28%28x%5E2%2B54x%2B729%29%2F1800%29
4.

+f-1%28x%29=%28%28x%5E2%2B54x%2B729%29%2F1800%29