Explanation
Step 1: Simplify the expression inside the modulus
First, let's factorize the quadratic expression inside the absolute value:
So the equation becomes:
Step 2: Establish the constraint
Since the left side is an absolute value (which is always ≥0), the right side must also be non-negative:
Step 3: Solve by cases
An equation ∣A∣=B is solved by considering A=B and A=−B.
Case 1: (x2−x−6)=x+2
Roots: x=4 and x=−2.
Check against constraint (x≥−2): Both 4 and −2 are valid.
Case 2: (x2−x−6)=−(x+2)
Roots: x=2 and x=−2.
Check against constraint (x≥−2): Both 2 and −2 are valid.
Step 4: List the unique roots
Collecting all the values of x found:
The distinct (unique) roots are x=−2,2, and 4.
Conclusion:
There are exactly 3 distinct roots satisfying the equation.
Correct Option: (b)