The product of the distinct roots of is
The product of the distinct roots of is
Solution
We have:
When we have an equation of the form , the expression inside the absolute value bars can be either positive or negative, but the result is always .
This gives us two cases:
Case 1: (when the expression is positive)
Case 2: (when the expression is negative)
We need two numbers that multiply to and add to . These numbers are and since and .
Therefore: or
Therefore: or
Since we have , the right side must be non-negative.
This means , so .
Checking our solutions:
:
:
:
All solutions are valid!
From our cases, we found:
Distinct roots means we only count each unique value once.
The distinct roots are:
Product of distinct roots =
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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