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3d Trig! (1 Viewer)

magik22

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Does anyone know a method on how to tackle a 3D trig question ESPECIALLY when there is no diagram given. Like is there a way or method that makes it easier to interpret the question?

I'm finding it so difficult to draw the diagram out properly to begin with before I can even answer to question. =.=

thx everyone.
 

gurmies

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if you have trouble drawing the diagram, try this. Draw a set of axis as if you were doing co-ordinate geometry. The x-axis remains perfectly horizontal, but the y-axis should be tilted to the right at about a 45 degree inclination. From the "origin" draw a perfectly vertical line. Now you have an easy to visualise 3-D diagram which you can label accordingly. Personally, this part of trigonometry usually loses me as well, but the more of them you do, they easier they become - there are only so many types of questions they can ask. If you need more explanation, i'll try provide a diagram.

NOTE: If there are bearings involved be sure to label the north, which will be slightly tilted!
 

youngminii

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gurmies said:
if you have trouble drawing the diagram, try this. Draw a set of axis as if you were doing co-ordinate geometry. The x-axis remains perfectly horizontal, but the y-axis should be tilted to the right at about a 45 degree inclination. From the "origin" draw a perfectly vertical line. Now you have an easy to visualise 3-D diagram which you can label accordingly. Personally, this part of trigonometry usually loses me as well, but the more of them you do, they easier they become - there are only so many types of questions they can ask. If you need more explanation, i'll try provide a diagram.

NOTE: If there are bearings involved be sure to label the north, which will be slightly tilted!
This.
Also, draw the triangles seperately, (AS WELL) so that you have a clearer understanding
I always get confused with the right angled parts until I seperately draw the triangles, usually ends up with 2 vertical plane and 1 horizontal (ie. two up-3d and one flat-2d). Makes it that much easier
 
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gurmies

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youngminii said:
This.
Also, draw the triangles seperately, (AS WELL) so that you have a clearer understanding
I always get confused with the right angled parts until I seperately draw the triangles, usually ends up with 2 vertical plane and 1 horizontal (ie. two up-3d and one flat-2d). Makes it that much easier
Yep, that helps as well!
 

Timothy.Siu

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also, try to draw the diagram roughly to scale so ur angles/bearings dont look messed up and trick you
happens a lot to me sometimes...like drawing 500m shorter than 300m.
 

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