Inflexion points (1 Viewer)

Joshmosh2

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If I find the second derivative for a function, and end up with something like
y'' = 6x -7
How can I find out the points of inflexion?
Also, how can I determine whether they are concave up or down?

For finding the points, I am assuming y'' = 0 and solve for x
and from there, depending on whether the the solution for x is positive or negative, that will determine concave up or down?
Not entirely sure.
Thanks.
 

Stygian

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for the y coordinate sub into f(x)
 

ConorDevaney

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when proving it a point of inflexion, you have to test for values above and below the "possible point go inflexion", otherwise you won't receive the full marks of the question
 

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