What is the sum of the squares of all the real roots of ?
Answer and explanation
Correct answer: A.
- Step 1: Let : , so or .
- Step 2: The real roots are and .
- Step 3: Their squares are , which add to .
Answer
.
Why not the others: counts each of and once instead of twice; counts only the roots ; is the square of the largest root only; is , which leaves out one of the four roots.
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