How Do I Invert These Two Functions




If I define u1(r1,r2)=(1/r1)+(1/r2) and u2(r1,r2)=1/(r2-r1). How would I
go about solving these two equations for r1(u1,u2) and r2(u1,u2), which
would constitute "inverting the functions"? Thanks In Advance!
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