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The set of all values of x satisfying the inequality $$\log_{\left(x+\frac{1}{x}\right)}\left[\log_2\left(\frac{x-1}{x+2}\right)\right]>0$$ is
Given, $$\log_{\left(x+\dfrac{1}{x}\right)}\left[\log_2\left(\dfrac{x-1}{x+2}\right)\right]>0$$
The first constraint for this inequality is:
i.)$$x+\dfrac{1}{x}>0$$
or, $$\dfrac{x^2+1}{x}>0$$
Now, $$x^2+1$$ is always positive
So, for $$\dfrac{x^2+1}{x}$$ to be positive, $$x$$ has to be positive i.e. $$x>0$$ ------>(1)
ii.)$$\log_2\left(\dfrac{x-1}{x+2}\right)>1$$
or, $$\dfrac{x-1}{x+2}>2^1$$
or, $$\dfrac{x-1}{x+2}-2>0$$
or, $$\dfrac{x-1-2x-4}{x+2}>0$$
or, $$\dfrac{-x-5}{x+2}>0$$
or, $$\left(x+5\right)\left(x+2\right)<0$$
or, $$-5<x<-2$$ ----->(2)
(1) and (2) are contradictory to each other
So, there is no value of $$x$$ possible satisfying this inequality
So, solution set is null set
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