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Sketching a curve (1 Viewer)

Monsterman

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How would I sketch x^3-2x^2+2x+5? like show how to find the stationary points?
Cause i differentiated it and completed the square and got 3((x-2/3)^2+10/9).. could someone confirm this cause i reckon i did it wrong..
 

nonsenseTM

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I got y'=3((x-2/3)^2)+2/3 which is always greater than 0 , so always increases

and point of non horizontal inflex. at 2/3,155/27, as x appoaches +/- infinity, y appoaches +/- infinity
 

Monsterman

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^
thats useless when you want to know how to do it for an exam........

I got y'=3((x-2/3)^2)+2/3 which is always greater than 0 , so always increases

and point of non horizontal inflex. at 2/3,155/27, as x appoaches +/- infinity, y appoaches +/- infinity
how do you know the position of the inflexion point? because if you let the derivative equal zero you get a negative 2/9 and a squareroot.. which equals gayness
 
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cutemouse

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Solve y'=0 for stat pts. Determine their nature (using y' or y'' sign test).

Solve y''=0 and check for concavity changes for inflexions.
 

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