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The set of all real numbers x for which x2 - |x + 2| + x > 0 is (2002)

1. (-∞, -2) ∪ (2, ∞) 2. (-∞, -√2) ∪ (√2, ∞)

3. (-∞, -1) ∪ (1, ∞) 4. (√2, ∞)

Solution: The condition given in the question is x2 - |x + 2| + x > 0

Two cases are possible:

Case 1: When (x+2) ≥ 0.

Therefore, x2 - x - 2 + x > 0

Hence, x2 – 2 > 0

So, either x √2.

Hence, x ∈ [-2, -√2) ∪ (√2, ∞) ……. (1)

Case 2: When (x+2)

Then x2 + x + 2 + x > 0

So, x2 + 2x + 2 > 0

This gives (x+1)2 + 1 > 0 and this is true for every x

Hence, x ≤ -2 or x ∈ (-∞, -2) ...…… (2)

From equations (2) and (3) we get x ∈ (-∞, -√2) ∪ (√2, ∞).

The set of all real numbers x for which x2 - |x + 2| + x > 0 is (2002)

1. (-∞, -2) ∪ (2, ∞) 2. (-∞, -√2) ∪ (√2, ∞)

3. (-∞, -1) ∪ (1, ∞) 4. (√2, ∞)

Solution: The condition given in the question is x2 - |x + 2| + x > 0

Two cases are possible:

Case 1: When (x+2) ≥ 0.

Therefore, x2 - x - 2 + x > 0

Hence, x2 – 2 > 0

So, either x √2.

Hence, x ∈ [-2, -√2) ∪ (√2, ∞) ……. (1)

Case 2: When (x+2)

Then x2 + x + 2 + x > 0

So, x2 + 2x + 2 > 0

This gives (x+1)2 + 1 > 0 and this is true for every x

Hence, x ≤ -2 or x ∈ (-∞, -2) ...…… (2)

From equations (2) and (3) we get x ∈ (-∞, -√2) ∪ (√2, ∞).

rahul , 8 Years ago
Grade 11
anser 1 Answers
Umang goyal

Last Activity: 8 Years ago

X^2 -|x+2|+X >0Two cases arises Case 1 when |X+2| >0So.X^2-X-2+X >0X^2>2(X-√2)(X+√2)>0---------(1)Case 2 when|X+2|0X^2 +x+2+x>0---------(2)SOLVING both equation we get the answers....
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