<PRE><B>Question 1144563</B>
The total resistance, R, in a parallel circuit with three resistances, R1, R2, and R3, is given by the formula

1 over R equals 1 over R subscript 1 plus 1 over R subscript 2 plus 1 over R subscript 3

Simplify the right-hand side of the equation.
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{{{1/R = 1/R1 + 1/R2 + 1/R3}}}
DEN = R1*R2*R3
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{{{1/R = (R2+R3)/DEN + (R1+R3)/DEN + (R1+R2)/DEN}}}
{{{1/R = 2(R1 + R2 + R3)/DEN
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I recommend doing theM 2 at a time:
For R1 &amp; R2:
R4 = R1*R2/(R1+R2)
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Then, R = R4*R3/(R4+R3)



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