# math 117/algebra

The combined resistance of two resistors R_(1 amd R_2 )in a parallel circuit is given by the formula R_(r= 1/(1/R_1 + 1/R_2 )) Simplify the formula. Help what is this talking about and how do I work it?

find R as a function fo r`1 and r2.

1/R= 1/r1 + `1/R2

R= ???

Get a common denominator on the right (r1r2), combine the fractions, then invert the left and right sides.

r= 1/(1/R_1 + 1/R_2 ) =

R_1 R_2/(R_1 + R_2)

1. 👍 0
2. 👎 0
3. 👁 46

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