Charge inside nested spheres

[phy_magic]

Homework Statement

Can someone explain why is in this task used calculations in space R3-R1 and than in space R3-R1.

Relevant Equations

So i try to solving with conetion with electric-field energy. So i calculate electric field in region r<R1, and in region R3>r>R2 and r>R3 , with respect that E=0 at r>>R3. Inside layer of conducting sphere E=0.

On picture is part of solution and other is task.

 

[haruspex]

Homework Statement: Can someone explain why is in this task used calculations in space R3-R1 and than in space R3-R1.

You wrote R3-R1 both times. What did you mean to write?

Relevant Equations: So i try to solving with conetion with electric-field energy. So i calculate electric field in region r<R1, and in region R3>r>R2 and r>R3 , with respect that E=0 at r>>R3. Inside layer of conducting sphere E=0.

I am unable to comment without seeing your whole solution.

On picture is part of solution and other is task.

Please post a translation of the text in the (partial) solution.

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