How would you approach this problem?
Thanks in advance.
"Is (x-y)/(x+y) > 1" doesnot mean that "is -y > y?".
it would be if both (x-y) and (x+y) were +ve. since we do not know, it could be or not.
1: if x > y, y is -ve, and x > lyl, then (x-y)/(x+y) > 1. if x > y, y is also +ve, then no. so nsf.
2: If x is +ve and x > lyl, then yes (x-y)/(x+y) > 1. If x is +ve but < lyl, then no. so nsf.
togather: also nsf cuz we have both conditions applied above.