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What are the roots of this equation: x^2 + 4x + 8 = 0?

A) -1i
B) -4i
C) –2 + 2i
D) -1 + 4i

User Babs
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1 Answer

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Final answer:

The roots of the quadratic equation x^2 + 4x + 8 = 0 are found using the quadratic formula. They are complex numbers, -2 + 2i and -2 - 2i, which corresponds to option C).

Step-by-step explanation:

To find the roots of the quadratic equation x^2 + 4x + 8 = 0, we can use the quadratic formula, which is given by:

x = [-b ± √(b^2-4ac)] / (2a)

In this equation, a = 1, b = 4, and c = 8. Plugging these values into the quadratic formula, we get:

x = [-4 ± √(4^2 - 4*1*8)] / (2*1)

x = [-4 ± √(16 - 32)] / 2

x = [-4 ± √(-16)] / 2

Since the square root of a negative number results in an imaginary number, we can rewrite √(-16) as 4i (where i is the imaginary unit).

Therefore:

x = [-4 ± 4i] / 2

x = -2 ± 2i

Thus, the roots of the equation are -2 + 2i and -2 - 2i, which corresponds to option C).

User Hinrik
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