Solve for k
k\in \left(-\infty,-\frac{1}{2}\right)\cup \left(0,\infty\right)
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\frac{1+2k}{k}>0
Divide both sides by -1. Since -1 is negative, the inequality direction is changed. Zero divided by any non-zero number gives zero.
2k+1<0 k<0
For the quotient to be positive, 2k+1 and k have to be both negative or both positive. Consider the case when 2k+1 and k are both negative.
k<-\frac{1}{2}
The solution satisfying both inequalities is k<-\frac{1}{2}.
k>0 2k+1>0
Consider the case when 2k+1 and k are both positive.
k>0
The solution satisfying both inequalities is k>0.
k<-\frac{1}{2}\text{; }k>0
The final solution is the union of the obtained solutions.
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