Can anyone please explain to me: x!=-y mean??????
in this question:
If x != -y, is (x-y)/(x+y) > 1
1. x>0
2. y<0
in this question:
If x != -y, is (x-y)/(x+y) > 1
1. x>0
2. y<0
x!=-y means x is not equal to y.
(x-y)/(x+y) > 1
=> (x-y)/(x+y) -1 > 0
or -2y/(x+y) > 0
a: x>0 insufficient because y can be + or -
b: y<0 insufficient because x can be + or - and x can be greater than or less than y
combining both a: and b:
if x>0 and y<0 and x>y we will have -2y/(x+y) > 0
if x>0 and y <0 and x < y, we will have -2y/(x+y) < 0
hence insufficient
IMO E
