clc
no=1.5*10^10
disp("no = "+string(no)+"/cm^3") //initializing value of electrons and hole per cm^3.
n=1*10^18
disp("n = "+string(n)+"/cm^3") //initializing value of number of electrons per cm^3.
p=(no^2/n)
disp("number of holes ,p=(no^2/n))= "+string(p)+" /cm^3")//calculation



//this is solved problem 2.1 of chapter 2.