SOLUTION: Find x if 9^x-1=27 and also find dy/dx if y=(6x^3-x^2-x-1)^9

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Question 981856: Find x if 9^x-1=27 and also find dy/dx if y=(6x^3-x^2-x-1)^9
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
If 9%5E%28x-1%29=27 ,
%283%5E2%29%5E%28x-1%29=27--->3%5E%282%28x-1%29%29=27--->3%5E%282x-2%29=3%5E3--->2x-2=3--->2x=3%2B2--->2x=5--->highlight%28x=5%2F2%29 .
Maybe it was expected that the problem would be solved using logarithms, as in
9%5E%28x-1%29=27-->log%283%2C9%5E%28x-1%29%29=log%283%2C27%29-->%28x-1%29log%283%2C9%29=3-->%28x-1%29%2A2=3-->x-1=2%2F3-->x=2%2F3%2B1--->highlight%28x=5%2F2%29 .

y=%286x%5E3-x%5E2-x-1%29%5E9