So we just were given some formulas and I am confused about this simple question(adsbygoogle = window.adsbygoogle || []).push({});

Find the differential length or distance between the two points.

P(2,pi/2,-1) and Q(5,3pi/2,5)

I know this

for cylindrical

dL = dp (ap) + p dphi (aphi) + dz (az)

So i would integrate

I have a few questions does it matter if for example for dp

i integrate from 2 to 5 or from 5 to 2?

also in the aphi part, there is a "p" which is not constant in my problem so how can i do the integral with respect to dphi when p is not constant!!!

can I even use this?

help

EDITED: MY TEXT USES A DIFFERENT NOTATION I POSTED ANOTHER QUESTION AND THE INDIVIDUAL ALSO HAD PROBLEMS WITH MY NOTATION I HOPE THIS DIAGRAM HELPS IT'S FROM MY TEXTBOOK:

http://img261.imageshack.us/img261/7998/53164335jl9.jpg [Broken]

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# Homework Help: Differential Length (Cylindrical Coordinates)

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