It can be shown that the radial distance of a light ray travelling along the z axiz of an optical fiber is described by the following equiation. d2r/dz2=(1/nr)*(dn/dr)
for the case where the index of refraction n=n0(1-ar2) and ar2,,1 find a solution of the differential equiation for r(z).

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explanation:

the entire statement is true and correct.  

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