Show that for any cubic function of the form $\displaystyle y=ax^3+ bx^2 +cx +d$, there is a single point of inflection where the slope of the curve at that point is $\displaystyle c-(b^2/3a)$
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u find second derivative of function f"=c-(b^2/3a)? and thn u sovle for wht? i dont even know i m rit or wronge
once you find the second derivative set it equal to 0 and solve for x
6a+2b=0
but solve it for x $\displaystyle x = \frac{-2b}{6a}$ Now replace x in the first derivative with the x you just solved for in the 2nd derivative and simplify
Originally Posted by ilovemymath 6a+2b=0 No, 6ax+ 2b= 0. Solve for x.
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