SOLUTION: Find f(2/3). f(x)=18x^-12x-3

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Question 109420This question is from textbook
: Find f(2/3). f(x)=18x^-12x-3 This question is from textbook

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Something is missing. You've written 18x^? Should a 2 be here? I'm going to assume that a 2 should be here.


f%28x%29=18x%5E2-12x-3 Start with the given function


f%282%2F3%29=18%282%2F3%29%5E2-12%282%2F3%29-3 Plug in x=2%2F3


f%282%2F3%29=18%284%2F9%29-12%282%2F3%29-3 Square2%2F3 to get 4%2F9


f%282%2F3%29=72%2F9-12%282%2F3%29-3 Multiply 18 and 4%2F9 to get 72%2F9


f%282%2F3%29=8-12%282%2F3%29-3 Reduce


f%282%2F3%29=8-24%2F3-3 Multiply 12 and 2%2F3 to get 24%2F3


f%282%2F3%29=8-8-3 Reduce


f%282%2F3%29=-3 Combine like terms


So when x=2%2F3, f%28x%29=-3