Question 1190751
If you mean:
if a= (b-1)/(b+1) and b= 1/c, express a in terms of c.
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{{{a = (1/c - 1)/(1/c + 1)}}}
{{{a = ((1-c)/c)/((1+c)/c)}}}
{{{a = (1-c)/(1+c)}}}

c <> -1 or 0, b <> -1