InterviewSolution
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Solve the system of equations in R.(|x + 2| – x)/x < 2 |
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Answer» Given as (|x + 2| – x)/x < 2 Now, let us rewrite the equation as |x + 2|/x – x/x < 2 |x + 2|/x – 1 < 2 On adding 1 on both sides, we get |x + 2|/x – 1 + 1 < 2 + 1 |x + 2|/x < 3 On subtracting 3 on both sides, we get |x + 2|/x – 3 < 3 – 3 |x + 2|/x – 3 < 0 So, clearly it states, x ≠ 2 therefore two case arise: Case 1: x + 2 > 0 x > –2 Now, in this case |x + 2| = x + 2 x + 2/x – 3 < 0 (x + 2 – 3x)/x < 0 – (2x – 2)/x < 0 (2x – 2)/x < 0 Now, let us consider only the numerators, we get 2x – 2 > 0 x > 1 x ϵ (1, ∞) ….(1) Case 2: x + 2 < 0 x < –2 In this case, |x + 2| = – (x + 2) -(x + 2)/x – 3 < 0 (-x – 2 – 3x)/x < 0 – (4x + 2)/x < 0 (4x + 2)/x < 0 Then, let us consider only the numerators, we get 4x + 2 > 0 x > – 1/2 But x < -2 From the denominator we have, x ∈ (–∞ , 0) …(2) From (1) and (2) ∴ x ∈ (–∞ , 0) ⋃ (1, ∞) |
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