SOLUTION: can anyone help/explain?! Given f(x) = 2x^2 - x + 4 find f(1/b) leave all exponents positive

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Question 709327: can anyone help/explain?!
Given f(x) = 2x^2 - x + 4
find f(1/b)
leave all exponents positive
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
Given f(x) = 2x^2 - x + 4
find f(1/b)
substitute 1/b in:
f(1/b) = 2(1/b)^2 - (1/b) + 4
f(1/b) = 2(1/b^2) - (1/b) + 4
f(1/b) = 2/b^2 - (1/b) + 4
f(1/b) = 2/b^2 - b/b^2 + 4b^2/b^2
f(1/b) = (2 - b + 4)/b^2
f(1/b) = (6-b)/b^2
or
f(1/b) = 6/b^2 - 1/b