/sci/ - Science & Math

Bros, what is the differential of arch if the curve is a line going on top and against the x axis??
My physichit book says it is dl=dx but it makes no sense to me why it isn't dl=-dx. I actually never was actually thought what to do when the curves weren't "regular" i.e. they weren't differentiable.
pic rel is the excersize. I dont understand what values should the limits take either....
the work i should calculate is of a force agaist the electrostatic force aka -1*the work of the electric force

>>11973255
here is the excersize. I dont understand what values should the limits take either....
the work i should calculate is of a force agaist the electrostatic force aka -1*the work of the electric force