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Wohzazz

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How accurate do you have to be with graphs, like regarding concavity, slopes at different sections and the size
How about min/max points, when do you know you have to find them? Inflexion?
How about the guide graph (the graph you draw to help you draw another harder graph). Same axes? Dotted? Different colour pen for it?
Also, does negative gradient (or positive) gradient on both sides of a turning point mean conclusively that it is a point of inflexion.

And is drawing graphs like

[the integral of] f(x) dx
in the syllabus

Thanks.
 

Affinity

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I would say you need to show symmetry, asymtopes, the correct concavity (up/down), intercepts and inflexion/stationary points if feasible.


if something requires you to solve a cubic don't bother finding the values, just mark down a point.

graphs of integrals and derivatives are in the syllabus
 
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Wohzazz

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Do you know what graphs have the methods for the integrals? I seem to find it. The arnold n fitzpatrick books are very simple
 

McLake

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Originally posted by Wohzazz
Do you know what graphs have the methods for the integrals? I seem to find it. The arnold n fitzpatrick books are very simple
Can you explain what you mean ...
 
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I think he wants a list of what points on f(x) mean e.g. f(x) = 0, f(x) >0, f(x)<0, f(x) undefined

Just remember that you're looking at a graph of the gradient of a function for any given x value.
 

McLake

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OK. if F(x) is the integral of f(x) then we note:

where f(x) crosses the x axis we have a stationary point.

when f(x) is above the x axis we have a +ve gradient, when below negative gradient.

the higher the (absoulte) value of x, the steeper the F(x) curve is at that point.

asyptopes are translated across as gradient assymptopes

Any more?
 
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as x -> infinity, x -> -infinity.
I don't really know how to phrase this in a good sounding way, but I generally just look at what f(x) approaches, and then translate that across to F(x). e.g. if f(x) approaches 0, F(x) will 'level out' sort of thing. Perhaps you'd like to make this sound better McLake.
 

Wohzazz

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Originally posted by McLake
Can you explain what you mean ...
I don't know what i wrote myself. I meant to ask whether anyone knew of textbooks that showed methods of doing integral graphs.
 

:: ck ::

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u mean primitive graphs?

they are usually straightforward ... use some logic :p
 

Wohzazz

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Logic? I got none....
..Well maybe a fair bit.
I think i need a book because i find it hard to find how the curve slopes at differents points on the graph; their gradients and stuff. Plus my teacher never looked at these questions ever, and i'm like wtf. The integral of e^x-e^-x. How do i sketch that?? So you see i dont get it, need a book. Plus its so hard to ask Qs in class because she talks and writes the whole time. Thus, why i need a tutor right now
 

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