Solve math Problem?

Question

When two resistors R1 and R2 are connected in parallel, the net
resistance satisfies the equation
1/R=1/R1+1/R2

Solve for R1 in terms of R and R2.

Now I think I have to subtract 1/R2, so i get 1/R1 by itself
So would it be 1/R1=1/R-1/R2, then reciprocal to R1=R-R2. Am I close or on the right track., some help would be grateful

Answer 1

1/R1=1/r-1/r2
=(r2-r)/r2*r
r1=(r2*r)/(r2-r)

Answer 2

1/R = 1/R1 + 1/R2

So 1/R1 = 1/R - 1/R2 = (R2 - R)/RR2

So R1 = RR2/(R2 - R)

You should not just invert ratios like what you attempted. Thus 1/2 + 1/2 = 1 and not 1/4 which would be the case if you simply invert the ratios and try to add.

Answer 3

If all you want to do is isolate R1:

1/R=1/R1+1/R2
1/R1 = 1/R - 1/R2
1 = R1*(1/R - 1/R2) = R1*((R2 - R) / R*R2)
R1 = R*R2/(R2 - R)

Answer 4

1 / R = 1 / R1 + 1 / R2
1/R1 = 1 / R - 1 / R2
1 / R1 = (R2 - R) / (R.R2)
R1 = (R.R2) / (R2 - R)

Answer 5

1/R=1/R1+1/R2
1/R1=1/R-1/R2
1/R1=(R2-R)/(R*R2)
R1=(R*R2)/(R2-R)