Question

Which expression is equivalent to the following complex fraction?

1/x-1/y / 1/x+1/y

A. y+x/y-x
B. (y-x)(y+x)/ x^2 y^2
C. x^2 y^2/ (y+x) (y+x)
D. y-x/y+x

Answer 1

The correct answer is D. y-x/y+x

Explanation:

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Answer 2

Answer: (D)
`(y-x)/(y+x)`

Explanation:

`((1)/(x)-(1)/(y))/((1)/(x)+(1)/(y))=((y-x)/(xy))/((y+x)/(xy))=(y-x)/(y+x)`

Just a note on writing down these expressions: I recommend using parentheses whenever you can to avoid misinterpretation. An expression 1/x-1/y / 1/x+1/y could be interpreted by someone as 1/x-(1/y / 1/x)+1/y, which is a different thing.