please explain how to solve this one?
my method..
take 1. since 1/(k-1) > 0, k-1 should be positive.
therefore, k-1 < 1
hence, k < 2 insuff.
take 2. since 1/(k+2) > 0 , k+1 should be positive.
therefore, k+1 < 1
hence k<0 suff.
hence B..
please lemme know what i did wrong??
my method..
take 1. since 1/(k-1) > 0, k-1 should be positive.
therefore, k-1 < 1
hence, k < 2 insuff.
take 2. since 1/(k+2) > 0 , k+1 should be positive.
therefore, k+1 < 1
hence k<0 suff.
hence B..
please lemme know what i did wrong??
- Attachments
-
















