Question

If the average number of electrons per atom in the conduction band is 1/3, then the Fermi energy is

Answer 1

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Answer 2

Explanation:

x^2+1/x^2=7

Add 2x.1/x on both sides

x^2+1/x^2+2*x*1/x =7+2*x*1/x

(x+1/x)^2= 9

x+1/x=+3

on cubing

x^3+1/x^3+3x^2*1/x+3x*1/x^2=+27

x^3+1/x^3+3x+3/x= 27

x^3+1/x^3+3(x+1/x)=27

x^3+1/x^3+9=27

x^3+1/x^3=18