I got an answer for this, but it just doesn't seem correct. Maybe someone could tell me what I am doing wrong, or that I am just over thinking the problem and I am right.(adsbygoogle = window.adsbygoogle || []).push({});

1. The problem statement, all variables and given/known data

Write an expression for the differential length vectordlat the point (1,2,8) on the straight line y=2x, z=4y, and having the projection dx on the x-axis

2. Relevant equations

dl=dxax+dyay+dzaz

3. The attempt at a solution

y=2x, z=4y, therefore z=8x

therefore

dxax+2dxay+8dxaz.

since there are no variables remaining after you take the derivative,dlis then

1ax+2ay+8az

Any help would be amazing, and please excuse me if I am just being a complete idiot.

Thanks

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# Find Differential Length

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