Can someone please let me know when I can flip and when I cannot flip a fraction in an inequality?
Typically, this is "unsafe" since the variable's sign is not known. However, in this problem, it appears necessary.
If not, is there another way to solve it? I tried doing the wavy line method after solving for two sides independently and trying to overlap, but it didn't work....
Problem:
If 3 6/(x+1) 6, find the range of x
My approach:
Because I don't know the sign of the expression (x+1), I resorted to solving two inequalities and seeing if there was an overlap:
3-6/(x+1) 0
and
06-6/(x+1)
The source (below) appears to reference the need to memorize some rule...but there must be a better way than this.
Thank you!
Source: crackverbal
gmat-inequalities/
Section: D) Reciprocal Inequalities![]()
Typically, this is "unsafe" since the variable's sign is not known. However, in this problem, it appears necessary.
If not, is there another way to solve it? I tried doing the wavy line method after solving for two sides independently and trying to overlap, but it didn't work....
Problem:
If 3 6/(x+1) 6, find the range of x
My approach:
Because I don't know the sign of the expression (x+1), I resorted to solving two inequalities and seeing if there was an overlap:
3-6/(x+1) 0
and
06-6/(x+1)
The source (below) appears to reference the need to memorize some rule...but there must be a better way than this.
Thank you!
Source: crackverbal
gmat-inequalities/
Section: D) Reciprocal Inequalities