Hope I've chosen the right level to post this:
As an old returner to maths I'm practicing equations again and having a problem with this question using fractions:
Make 'R' the subject:
1/R = 1/R1 + 1/R2 .....................................[edited]
I had a go doing this which might be bizarre and incompetent: 1/R = R^-1 = R1^-1 + R2^-1
R^-1 x R^2 = R1^-1 X R^2 + R2^-1 +R^2 =
R = R^2(R1^-1 + R2^-1)
but that isn't the right answer!
So I then tried:
1/Rx R^2 = R^2/R = R so:
R = R^2/R1 + R^2/R2 then:
R = (R^2R2 + R^2R1)/R1R2
But that wasn't right! Help appreciated!
As an old returner to maths I'm practicing equations again and having a problem with this question using fractions:
Make 'R' the subject:
1/R = 1/R1 + 1/R2 .....................................[edited]
I had a go doing this which might be bizarre and incompetent: 1/R = R^-1 = R1^-1 + R2^-1
R^-1 x R^2 = R1^-1 X R^2 + R2^-1 +R^2 =
R = R^2(R1^-1 + R2^-1)
but that isn't the right answer!
So I then tried:
1/Rx R^2 = R^2/R = R so:
R = R^2/R1 + R^2/R2 then:
R = (R^2R2 + R^2R1)/R1R2
But that wasn't right! Help appreciated!
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