How to position negative sign of fractionFor example we have: − 1 2 Does this mean that only the numerator of the fraction is negative?Can we put it like this? − 1 2 Does this means that the whole fraction is negative?And then can we put it like this? 1 − 2 Does this mean that only the denominator of the fraction is negative?Do the above suggestions [look] right? Or how should I understand when in some examples the minus sign is moving from numerator to the whole fraction?

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How to position negative sign of fractionFor example we have:            −      1        2  Does this mean that only the numerator of the fraction is negative?Can we put it like this?  −      1    2  Does this means that the whole fraction is negative?And then can we put it like this?      1          −      2      Does this mean that only the denominator of the fraction is negative?Do the above suggestions [look] right? Or how should I understand when in some examples the minus sign is moving from numerator to the whole fraction?

Gerardo Barry · Accepted Answer

You might want to ask yourself what is meant when you put a minus sign in front of something. The answer could be, for example, that   −      a    b   is the solution to the equation  x  +      a    b    =  0where the unknown is x. Now, you want to know whether             −      a        b    is the same as    −      a    b  . Just check if it solves the equation!            −      a        b    +      a    b    =            −      a      b      +      a      b              b      2        =      0          b      2        =  0But lo and behold, the same goes for        a          −      b             a          −      b        +      a    b    =            a      b      +      a      (      −      b      )              (      −      b      )      (      b      )        =            a      b      −      a      b              −              b        2              =      0          −              b        2              =  0We conclude that both             −      a        b   and       a          −      b       are opposites of the number       a    b  , i.e. they are both   −      a    b  . This works because of the way that fractions and their operations are defined. Note that I have used a primitive way of adding fractions, by taking as the common denominator the product of denominators (to avoid using known tricks).

Brooklynn Hubbard · Accepted Answer

The value is the same for all three versions, although the value might be seen as the result of a different operation:                                          −            a                    b                                    =                              (            −            a            )                    b                =        (        −        a        )                  /                b        =        −        (        a                  /                b        )                            −                  a          b                                    =        −                  (                      a            b                    )                =        −        (        a                  /                b        )                                      a                      −            b                                              =                  a                      (            −            b            )                          =        a                  /                (        −        b        )        =        −        (        a                  /                b        )            The middle version is the most symmetric and IMHO most often used, the other version might show up during calculations or in explanations how one calculates with fractions.

How to position negative sign of fraction For example we have: −<!-- − --

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