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

Find a point P on y=x^{3}such that the tangent at P intersects the original curve again at point Q so that the slope of the tangent at Q is 4 times the slope of the tangent at P.

2. Relevant equations

y'=3x^{2}

and the slope of the what I think it should be a secant line=(y2-y1)/(x2-x1)

3. The attempt at a solution

I figured that 2P=Q because 3P^{2}=(3/4)Q^{2}and then by using algebra I expressed Q in terms of P.

I know this leads to somewhere, but im not sure what should I do next.

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# Homework Help: A Quesiton on Derivatives

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