Worked solution
Use either a difference graph or a denominator sign test
Find the set of values of x satisfying .
CJC · Lecture · Example 6
Method 1: graph one difference
Bring the right side to the left: . Sketch . It has vertical asymptotes x=−2 and x=0, horizontal asymptote y=1 and no x-intercepts. The first and third branches are positive; the middle branch is negative. Thus . To decide this inequality, focus on the branch signs and poles; turning-point coordinates are not needed.
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Method 2: reduce to a sign test
The left side is . Since x²+2>0 for every real x, require . Signs around −2,0 are +,−,+. The solution set is . Neither pole is allowed, and equality never occurs because the numerator is positive.
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Common mistakes
The ≥ sign does not make an undefined denominator value admissible.