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The product of the distinct roots of ∣x2−x−6∣=x+2|x^2 − x − 6| = x + 2 is

Solution

✅ Correct Option: 4

We have: ∣x2−x−6∣=x+2|x^2 - x - 6| = x + 2

When we have an equation of the form ∣A∣=B|A| = B, the expression inside the absolute value bars can be either positive or negative, but the result is always BB.

This gives us two cases:

Case 1: x2−x−6=x+2x^2 - x - 6 = x + 2 (when the expression is positive)

Case 2: x2−x−6=−(x+2)x^2 - x - 6 = -(x + 2) (when the expression is negative)


x2−x−6=x+2x^2 - x - 6 = x + 2

x2−x−6−x−2=0x^2 - x - 6 - x - 2 = 0

x2−2x−8=0x^2 - 2x - 8 = 0

We need two numbers that multiply to −8-8 and add to −2-2. These numbers are −4-4 and +2+2 since −4×2=−8-4 \times 2 = -8 and −4+2=−2-4 + 2 = -2.

(x−4)(x+2)=0(x - 4)(x + 2) = 0

Therefore: x=4x = 4 or x=−2x = -2


x2−x−6=−(x+2)x^2 - x - 6 = -(x + 2)

x2−x−6=−x−2x^2 - x - 6 = -x - 2

x2−x−6+x=−2x^2 - x - 6 + x = -2

x2−6=−2x^2 - 6 = -2

x2=4x^2 = 4

Therefore: x=2x = 2 or x=−2x = -2


Since we have ∣x2−x−6∣=x+2|x^2 - x - 6| = x + 2, the right side must be non-negative.

This means x+2≥0x + 2 \geq 0, so x≥−2x \geq -2.

Checking our solutions:

x=4x = 4: 4+2=6≥04 + 2 = 6 \geq 0

x=−2x = -2: −2+2=0≥0-2 + 2 = 0 \geq 0

x=2x = 2: 2+2=4≥02 + 2 = 4 \geq 0

All solutions are valid!


From our cases, we found: x=4,−2,2,−2x = 4, -2, 2, -2

Distinct roots means we only count each unique value once.

The distinct roots are: 4,2,−24, 2, -2


Product of distinct roots = 4×2×(−2)=−164 \times 2 \times (-2) = -16

We multiply all unique solutions together, counting each distinct value only once, regardless of how many times it appeared in our cases.

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