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# Explain how i and j notation works please? watch

1. (Original post by Vikingninja)
The hats are for in the direction. Without the hats is for the position as in for a location.
I don't see how this makes sense. The hats are for unit vector. Not for in the direction.
2. (Original post by Zacken)
I don't see how this makes sense. The hats are for unit vector. Not for in the direction.
As in the vector in that direction. e.g. 6i^ has a length of 6 in the x direction. As far as I'm aware without the hat is the position of a graph, e.g. 6i on a graph is at 6 on the x direction
3. (Original post by Vikingninja)
As in the vector in that direction. e.g. 6i has a length of 6 in the x direction.
Yeah, I know. I was questioning the use of v/s .
4. (Original post by Zacken)
Yeah, I know. I was questioning the use of v/s .
Just edited the second part afterwards. With no hat its not a vector but a position. Some questions will give two points with i, j and k and you need to work out the vector between them.
5. (Original post by Vikingninja)
As in the vector in that direction. e.g. 6i^ has a length of 6 in the x direction.
this

and
As far as I'm aware without the hat is the position of a graph, e.g. 6i on a graph is at 6 on the x direction
this

are the exact same things.
6. (Original post by Zacken)
this

and this

are the exact same things.
What I mean with the hat is that its a vector/length in that direction, without the hat its a position and does not create a length along that direction. Between two points the vector would have hats as its a length.

With my example of without the hats its at a position of 6 in the x direction and would be 6 from the origin if it were a unit vector.
7. (Original post by Vikingninja)
What I mean with the hat is that its a vector/length in that direction, without the hat its a position and does not create a length along that direction. Between two points the vector would have hats as its a length.
Draw the position vector . It's an arrow starting from the origin and extends upwards 6 units.
8. (Original post by Zacken)
Draw the position vector . It's an arrow starting from the origin and extends upwards 6 units.
Oh right then, I'll need to read up my vectors then.
9. (Original post by Zacken)
Draw the position vector . It's an arrow starting from the origin and extends upwards 6 units.
With standard orientation of the axes it extends right, not upwards.
10. (Original post by morgan8002)
With standard orientation of the axes it extends right, not upwards.
I was thinking of complex numbers.
11. (Original post by Zacken)
I was thinking of complex numbers.
Another reason I prefer the hat version.
12. (Original post by morgan8002)
Another reason I prefer the hat version.
Good point...
13. (Original post by morgan8002)
Another reason I prefer the hat version.
I like hats, but not i,j,k.
It's all about , etc.

(I'm currently doing some work on suffix notation and using the numbers rather than x,y,z or i,j,k makes things a lot easier later on down the line )
14. (Original post by rayquaza17)
I like hats, but not i,j,k.
It's all about , etc.

(I'm currently doing some work on suffix notation and using the numbers rather than x,y,z or i,j,k makes things a lot easier later on down the line )
Had some notes using e^i and a few months later I have no clue what I was on about

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15. (Original post by drandy76)
Had some notes using e^i and a few months later I have no clue what I was on about

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or ? Two very different things!
16. (Original post by rayquaza17)
or ? Two very different things!
The latter

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17. (Original post by drandy76)
The latter

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Orthogonal vectors that form a orthonormal basis. (from what little I know, somebody jump in and correct me! )
18. (Original post by Zacken)
Orthogonal vectors that form a orthonormal basis. (from what little I know, somebody jump in and correct me! )
From what I recall they're components? I'll check tomorrow and get back to you but I recall reading about them to show why vector addition works

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19. (Original post by drandy76)
From what I recall they're components? I'll check tomorrow and get back to you but I recall reading about them to show why vector addition works

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Yeah like e_1 is the same as x. It's just a different way of writing it. (No latex as I'm on my phone, sorry)
20. (Original post by rayquaza17)
Yeah like e_1 is the same as x. It's just a different way of writing it. (No latex as I'm on my phone, sorry)
And the I denotes which unit vector it denotes right, so e_3 would be equivalent to k?

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