Question 993120
R=1/r1+1/r2+1/r3 i need r2
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1/r2 = R - (1/r1) - (1/r3)
{{{r2 = 1/(R - (1/r1) - (1/r3))}}}
{{{r2 = 1/(R - (r1 + r3)/(r1*r3))}}}
{{{r2 = 1/((R*r1*r3 - r1 - r3)/(r1*r3))}}}
{{{r2 = r1*r3/(R*r1*r3 - r1 - r3)}}}