Conversion of cartesian coords to spherical polars

[kelbear]

Homework Statement

Velocity vector, v:

v = (yi + xj) / (x^2 + y^2 + z^2)^(3/2)

"Re write "v" in spherical polar coordinates and unit vectors"

Homework Equations

Obviously
r = (x^2 + y^2 + z^2)^(1/2)
theta = tan^(-1)((x^2 + y^2)^(1/2)/z)
phi = tan(^-1)(y/x)

The Attempt at a Solution

Have tried rearranging the expression for v and substituting using the above formulae but not getting anywhere. I know its a simple question but am obviously missing something basic.
Any help is very much appreciated x

 

[tiny-tim]

welcome to pf!

hi kelbear! welcome to pf!

(have a theta: θ and a phi: φ and a square-root: √ and try using the X² and X₂ icons just above the Reply box )

"unit vectors" means e_r and e_θ, the unit vectors in the radial and transverse directions

(so for example e_r = r/r)