//Example number 7.1, Page number 7.12

clc;clear;close

// Variable declaration
R=poly([0],'R')
a=2*R // // unitless

// Results
disp(1/a^2,"i)Number of atoms per unit area of (100)plane=")
disp(1/sqrt(2)*a^2,"ii)Number of atoms per unit area of (110)plane=")
disp(1/sqrt(3)*a^2,"iii)Number of atoms per unit area of (111)plane=")