Question:
If the roots \(x^2 + ax + 9 = 0\) are complex, then
If the roots \(x^2 + ax + 9 = 0\) are complex, then
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For complex roots: discriminant must be negative.
Updated On: Apr 18, 2026
- \(a<6\)
- \(a<-6\)
- \(|a|<6\)
- \(|a|>6\)
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The Correct Option is C
Solution and Explanation
Concept:
Complex roots when discriminant \( < 0 \).
Step 1: Discriminant.
\[ D = a^2 - 36 < 0 \] \[ a^2 < 36 \Rightarrow |a| < 6 \]
Step 1: Discriminant.
\[ D = a^2 - 36 < 0 \] \[ a^2 < 36 \Rightarrow |a| < 6 \]
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