Geometrical applications of Calculus! Curve Sketching Q. (1 Viewer)

g4geexa

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Do you put a scale in your sketch???
Im not sure because we don't normally find the x-intercepts, and we may end up contradicting ourselves..

What are your thoughts??

Do you just plot known pts? (stationary pts, points of inflection, end points etc..)
 

tommykins

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you ALWAYS plot intercetps (x and y) and stationary points whre specified.

all assymptotes need to be labeled.
 

Michaelmoo

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tommykins said:
you ALWAYS plot intercetps (x and y) and stationary points whre specified.

all assymptotes need to be labeled.
The only exception I think would be for a circle with centre other than the origin. In that case you don't need x/y intercepts, just centre, and a point indicating the radius.
 

Trebla

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Labelling axes, intercepts and asymptotes is a must if they're easy to find. Turning points and inflexion points should be labelled only if the question requires you to do so or you found them in an earlier part of the question.
 
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tommykins

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lol, once you do 4unit you'll need to label all intersections because you deal with ellipses.
 

g4geexa

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Okay, say we have.. 2x^3 - 4x^2 -12X + 5

In that case, the x intercepts would be too hard to find.
Of course I would lable the y intercept and all neccessary points on the graph... but do I put in a scale for it?

If I don't know the x intercepts won't I end up contradicting myself???
 

tommykins

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nah you normally just do a rough sketch (ie. the shape), don't have to be pedantic and make like 1cm = 1 unit or anything.
 

g4geexa

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Yeah alright that sound logical. I don't think they're gonna be too worried if I put a scale on the axes anyway.
 

Michaelmoo

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tommykins said:
lol, once you do 4unit you'll need to label all intersections because you deal with ellipses.
Yer lol, but you don't have to bother with 2 unit circles
 

shaon0

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Michaelmoo said:
Yer lol, but you don't have to bother with 2 unit circles
Oh crap. Why do i label all my circl'e intersections of axes. :(
 

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