Question 1085970
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Your expression is <U>THIS</U>:

{{{y/(y+1)}}} = {{{1 - 1/(1+y)}}}.


Move the fraction {{{1/(1+y)}}} from the right side to the left (with the sign change, of course). You will get

{{{y/(y+1)}}} + {{{1/(y+1)}}} = 1.


Add the two fractions in the left side with common denominator (y+1).


You momentarily will get that the left side is identical to the right side.


Did I convince you ?
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