If k not equal to 0, 1, or -1, is 1/k >0?

stmt A. 1/k-1 > 0
stmt B. 1/k+1 > 0

The answer is Stmt A.

Can someone explain why stmt B is not sufficent?

Hi, Please see my explanation below -

Given questions :

If k not equal to 0, 1, or -1, is 1/k >0?

stmt A. 1/k-1 > 0
stmt B. 1/k+1 > 0

Let us take statement I - In this, it is given that 1/(k-1) >0. This implies that k must be postive and k must be greater than 1. Hence, 1/k is definitely greater than zero. For example, k's value is 2, then 1/(2-1) = 1 which is > 0. This implies that 1/2 = 0.5 which si still greater than '0'. Hence, this is sufficient.

Let us take II - It says 1/ (k+1) > 0 which means that this will satisfy for both positive and negative values of k which are less than -1. for example, if k is 2, 1/(k+1) is >0 and 1/k wll be >0. But if k's value is -0.5, it will satisfy the second equation but 1/k will be -2 which is <0 and hence, INSUFFICIENT.

Hence, A alone is sufficient to answer this question.

Hope this helps.

got it. thank you.

good explanation.

you made a false substitution of one word (corrected below in red) - it's a rather important word, which is why i'm posting a correction.
otherwise, perfect.