# Ejercicio 07.11

kill(all)$

R=rho*(L/s);

's=s:pi*r^2;    'rho=rho:(k*pi)/L;

R=rho*(L/s);

R(r):=k/(r^2);

dR(r)=diff(R(r),r);

dR(r)=R(r);

k=R*r^2;

dR(r)=-2*R/r*(dr);

abs(dR(r)/R)=abs(-2*(dr/r));

abs(dr/r)=erelradi:3.45*(10^-2);

abs(dR(r)/R)=2*erelradi,numer;