What is the sum of the squares of the roots of x^2 + 2x - 3 = 0?
Answer and explanation
Correct answer: B. 10
- Step 1: By Vieta, the sum of the roots is -2 and their product is -3.
- Step 2: x1^2 + x2^2 = (x1 + x2)^2 - 2 x1 x2 = 4 - (-6) = 10.
Answer
10.
Why not the others: 4 is the square of the sum; -2 adds 2p instead of subtracting it.
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