Using the differential length, dl, find the length of this curve: ρ = 3 , π/4

Question

Using the differential length, dl, find the length of this  curve: ρ = 3 , π/4 < Φ < π/2, z=constant

amistre64 · Answer

how can rho be constant and z be constant unless we are making a cone, with a circumference ?

amistre64 · Answer

rho is a hypot, z is a leg, and the radius of our cones base is the other leg, as i see it.

pythag to determine radius

anonymous · Answer

but how should I solve using differential length?

amistre64 · Answer

the sum of the approximate linear measures around a curve,  ive called them ds i think in my courses.

its either that or i just dont have a grasp on your terminology here.

anonymous · Answer

okay, i'll try to figure it out.

ds is for differential surface area though.... and I'm looking for dL, differential length of the curve

amistre64 · Answer

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s measures the length of the curve section as a linear approximation

integral of ds = integral of sqrt( dx^2 + dy^2) dt

amistre64 · Answer

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