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Find the range of values of k for which the equation 2x^2 + 6x + k = 0 has no real roots.

a) k < 3
b) k > 6
c) k ≤ 3
d) k ≥ 6

1 Answer

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Final answer:

The range of values of k for which the equation 2x^2 + 6x + k = 0 has no real roots is k > 4.5.

Step-by-step explanation:

To find the range of values of k for which the equation 2x^2 + 6x + k = 0 has no real roots, we can use the discriminant formula. The discriminant is given by b^2 - 4ac, where a, b, and c are the coefficients of the quadratic equation. Since we want the equation to have no real roots, the discriminant should be negative. Substituting the values a=2, b=6, and c=k, we have 6^2 - 4(2)(k) < 0



Simplifying, we get 36 - 8k < 0



To solve this inequality, we isolate k by subtracting 36 from both sides and dividing by -8. Thus, we have k > 4.5.



Therefore, the range of values of k for which the equation 2x^2 + 6x + k = 0 has no real roots is k > 4.5.

User Alessio Dal Bianco
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