"At what points, if any, are the tangents to the graph f(x)=x^2-3x horizontal?"(adsbygoogle = window.adsbygoogle || []).push({});

I know how to figure this out using a graphing calculator and using the 'short-cut' (nx^n-1), but I can't do it using limits. Help!

I'd like to use the equation lim x->a = f(x) - f(a) / x - a

Thanks!

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# Are any tangents to the graph f(x)=x^2-3x horizontal?

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