How does:
1 / (a+b / ab)
become:
ab / a + b
Is there a fraction rule I am not aware of?
2007-04-23 05:04:49 · 13 answers · asked by 19850421 1 in Science & Mathematics ➔ Mathematics
when you divide by a fraction, it's the same as multiplying by the reciprocal.
1 / [a+b / ab]
= 1 * (ab/a+b)
= ab / a+b
2007-04-23 05:08:53 · answer #1 · answered by Mathematica 7 · 1⤊ 0⤋
The rule when dividind by a fraction is to invert the fraction and multiply.
Exxmple
8 / (1/2) = 8 x (2/1) = 16 (correct answer)
Thus 1 / (a + b) / (ab) = 1 x ab / (a + b) = ab / (a + b)
2007-04-23 05:19:23 · answer #2 · answered by Como 7 · 0⤊ 0⤋
Placing a "1" above any fraction creates a recriprocal.
Multiply the top and bottom by the denominator for the first step to solve it. This creates another fraction that has the original denominator over the original denominator squared. When dividing fractions, invert and multiply:
(a+b)/ab * (ab)squared/(a+b)squared
When you multiply and cancel out common factors, you arrive at ab/(a+b)
2007-04-23 05:22:12 · answer #3 · answered by zombiehive 4 · 0⤊ 0⤋
1/ a+b becomes ab because a comes after b in the alphabet so it's like their neighbors/ best friends, you know... Now if b were to come before a, than it would be b+a/ ba. Now you always have to "+" the two numbers together to make them mesh well and become ab or ba (if b became before a in the alphabet). Now if you had abc, it would be a+b+c = abc which is really a standard term for the alphabets (we always tell small children to learn your "abc's" etc.. Also a+b is like saying 1+2, same rules apply. So ab+ a+b + a/b and b/a to equal ab+ba+a/b/b/a. Hope this helps.
2007-04-23 05:12:35 · answer #4 · answered by Anonymous · 0⤊ 1⤋
When dividing by a fraction, you can instead multiply it by the inverse of that fraction.
1 / (a + b) /ab becomes:
1 * ab/(a + b), which equals, ab/(a + b)
2007-04-23 05:09:20 · answer #5 · answered by Joy M 7 · 0⤊ 0⤋
What is 2^(-1) ie 2 raised to the power -1?
It is 1/2 right?
Then what is 1/2 raised to the -1?
2
So 1/(1/2) = 2
1 / (a+b / ab) = ab / (a + b)
2007-04-23 05:09:35 · answer #6 · answered by Dr D 7 · 0⤊ 0⤋
In general, 1 / (1/x) is equal to x. So that's the rule being applied here.
To see why this is true, notice that if you multiply the top and bottom of 1 / (1/x) by x, you get [ x ] / [(1/x)*x] = x / 1 = x.
2007-04-23 05:14:59 · answer #7 · answered by Anonymous · 0⤊ 0⤋
a million) 3/sixteen ÷ 5/8 = 3/sixteen x 8/5 = (3 x 8)/(sixteen x 5) = (3 x a million)/(2 x 5) = 3/10 2) 2/5 + a million/2 = (2 x 2)/(5 x 2) + (a million x 5)/(2 x 5) = 4/10 + 5/10 = 9/10 3) 5/6 x 8/15 = (5 x 8)/(6 x 15) = (a million x 8)/(6 x 3) = (a million x 4)/(3 x 3) = 4/9
2016-10-13 06:52:55 · answer #8 · answered by lishego 4 · 0⤊ 0⤋
1 / (a+b) /ab
When you reciprocate and multiply the equation it will look like this :
1 * ab/a+b= ab/a+b
2007-04-23 05:53:38 · answer #9 · answered by Dave aka Spider Monkey 7 · 0⤊ 0⤋
(1/a) / (1/b) = 1/a X b/1 = b/a
1/a/b = 1/1 X b/a = b/a
open your algebra book and you will learn more.
2007-04-23 05:23:30 · answer #10 · answered by hacker_lexy 3 · 0⤊ 0⤋