Why Do We Keep the 2x(hat) for E3?

[Marcin H]

Homework Statement

Find E1, E3, and ps2

Homework Equations

boundary conditions

The Attempt at a Solution

(these are class notes)[/B]
I understand how to find E1, but I am a bit confused about the reasoning behind finding E3... Why do we leave the 2x(hat) for E3...? I though that only tangential components of E don't change across a charge density, but the normal does change which is why we have to use boundary conditions and n (dot) (D1-D2)... But we don't have ps here so we can't use that. Why do we keep the 2x(hat)? I get the y(hat) and z(hat) part because they are tangential, but not the x(hat).

 

[kuruman]

The problem statement that you posted is somewhat unconventional. Can you clarify it using a few more English words?

 

[Marcin H]

The problem statement that you posted is somewhat unconventional. Can you clarify it using a few more English words?

I figured it out. I was in a hurry and forgot to explain the problem at the top. Sorry bout that!