Hello: I did take some university math years ago, but now approaching 50 yrs old, so am pretty rusty on a problem I'm trying to solve.

I am trying to choose coefficients for a 2nd equation to make the curve of it's solution as close as possible to a first equation,

particulary in the region of interest for 15<x<75.

The first equation is y=10*(1/((x/15) - 1)) for (15<x<300)

The second equation is y=-T*ln(1 - d/(x*0.002)), also for (15<x<300). I need to keep d > 0.03, T can be any reasonable positive value.

Thanks,

PT