Why Use i, j, and k as Unit Vectors Instead of x, y, and z?

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Why are i, j, and k perfered in many texts to represent the 3 spatial dimensions instead of (what seems to me to be more intuitive) x, y, and z?
 
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tony873004 said:
Why are i, j, and k perfered in many texts to represent the 3 spatial dimensions instead of (what seems to me to be more intuitive) x, y, and z?
By convention, i, j, k are vectors. x, y, z are coordinates. So you might have (in a cartesian coordinate system)
[tex]\textbf{r} = x\textbf{i} + y\textbf{j} + z\textbf{k}[/tex]
Follow Nabeshin's link for more.
 
It's just a convention. There's no special reason for it, probably other than the fact that they are less confusing than using [tex]\mathbf{ \hat{x}}[/tex] [tex]\mathbf{ \hat{y}}[/tex] and [tex]\mathbf{ \hat{z}}[/tex]
 
By convention, i, j, k are vectors.

More than that, they are unit vectors.

x. y and z extend from minus infinity to plus infinity.
 
Studiot said:
More than that, they are unit vectors.

x. y and z extend from minus infinity to plus infinity.

Sorry, I kinda lost track of this thread, even thought it was my question. I was just tutoring someone in Physics, and her teacher used x-hat, y-hat, and z-hat. But unit vectors make total sense. Thanks everyone for the replies.