It's often easier to see what's going on if we use numbers.brood1989 wrote:Well this is sad but I've got to ask. OG states that
1/k + 1/r is = to r/kr + k/kr (or r + k / kr) For
some reason I'm just not seeing this, can anyone explain
to me what they're doing?
For example, to add 1/3 + 1/4, we need a common denominator.
Here the common denominator is 12, so we'll take 1/3 and create an equivalent fraction by multiplying top and bottom by 4 to get 4/12
Similarly, we'll take 1/4 and create an equivalent fraction by multiplying top and bottom by 3 to get 3/12
So, 1/3 + 1/4 is the same as 4/12 + 3/12
Now that we have the same denominators, we can add the numerators to get (4+3)/12 or just 7/12
Now the exact same steps apply to 1/k + 1/r (we still need a common denominator to add these two fractions). Here, the common denominator is kr
So we'll take 1/k and create an equivalent fraction by multiplying top and bottom by r to get r/kr
Similarly, we'll take 1/r and create an equivalent fraction by multiplying top and bottom by r to get r/kr
So, 1/k + 1/r is the same as r/kr + k/kr
Now that we have the same denominators, we can add the numerators to get (r+k)/kr.
