//chapter12,Example12_3,pg 357

NA=0.5

n1=1.54

n2=sqrt((n1^2)-(NA^2))

printf("refractive index of cladding\n")

printf("n2=%.2f ",n2)

n=(n1-n2)/n1//relative change in refractive index of core

printf("\nrelative change refractive index of core\n")

printf("n=%.2f ",n)