Algebrahard · Past Paper
For what k does x^2 - kx + 1 = 0 have no real roots?
A|k| < 2
B|k| > 2
Ck = 2
Dk = -2
✓ Correct Answer: A — |k| < 2
No real roots if D < 0. k^2 - 4 < 0 => k^2 < 4 => -2 < k < 2, or |k| < 2.
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✓ Correct Answer: A — |k| < 2
No real roots if D < 0. k^2 - 4 < 0 => k^2 < 4 => -2 < k < 2, or |k| < 2.
Share this question