(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

This is exactly how this was written on the quiz today:

If f(1)=1 and f'(x)=(1/3) when x=1, find d/dx[f(2x^{2}-x)].

2. Relevant equations

Basic derivative rules (i.e., power rule).

3. The attempt at a solution

The first statement simply determines that f(2x^{2}-x) is true. When taking the derivative of f(2x^{2}-x), you get 4x-1. However, f'(1)=(1/3). When 1 is entered into 4x-1, (1/3) is clearly not the answer. I listed my answer as 12x-3, by setting 4x-1=(1/3), but I'm not sure if this is correct.

Is my professor insane or is this just a trickily worded question?

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# Homework Help: Very obscure/confusing question on quiz today

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