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differentiation shapes of curves

I have a graph y=3x^{4}-8x^{3}+6x^{2}+1

A question is asking me for the values of x for which the graph is concave upwards.

It has a minimum at (0,1) and a point of inflection going up at (1,2).

Minimums are concave upwards and +ve inflection points are concave upwards only after the inflection point.

I understand what it is asking me but there is a problem. The region of the graph between the minimum and the inflection - is it concave upwards or downards?
Original post by Sasuto
I have a graph y=3x^{4}-8x^{3}+6x^{2}+1

A question is asking me for the values of x for which the graph is concave upwards.

It has a minimum at (0,1) and a point of inflection going up at (1,2).

Minimums are concave upwards and +ve inflection points are concave upwards only after the inflection point.

I understand what it is asking me but there is a problem. The region of the graph between the minimum and the inflection - is it concave upwards or downards?


Concave down. https://www.desmos.com/calculator/mu0owkeozj

Concave up means f’’(x) > 0 so you can skip past the whole minimum / point of inflection analysis and just solve this inequality for the answer.
(edited 9 months ago)
Reply 2
Original post by RDKGames
Concave down. https://www.desmos.com/calculator/mu0owkeozj

Concave up means f’’(x) > 0

Oh yeah!!! I was solely thinking about the graphical shape and was confused. Thanks for replying, it's kinda late so I was totally not expecting this. Thanks so much!

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