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I saw this question and with my basic knowledge of differentiation I don't know what it means. $\frac{d}{dx}(x^2)$ where $x=3$

Where would I start to solve this?

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    It means: What is the value of the derivative of $y=x^2$ at the point when $x=2$? If you only know derivatives as limits, you are being asked to find $$\lim_{h\to 0}\frac{(3+h)^2 - 3^2}{h}.$$ If you already know the Power Rule, it's asking you to use the general formula for $\frac{d}{dx}(x^2)$, and plug in $x=3$ to get the value of the derivative at the point. Remember that the derivative at a point is just a number (the slope of the tangent to the graph at the point with $x$-coordinate $3$).2011-11-14
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    @ArturoMagidin In your first sentence, do you mean $x=3$? [I cannot comment and so I had to create an answer]2011-11-14
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    @psp: Good catch! Yes.2011-11-14

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