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"State the number of complex roots and the possible number of real and imaginary roots for each equation. Then find all roots.

b) (x - 2)(x + 2)(x^2 + 4) = 0"

User Docstero
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Final answer:

The equation (x - 2)(x + 2)(x^2 + 4) = 0 has two real roots, x = 2 and x = -2, and two imaginary roots, x = 2i and x = -2i.

Step-by-step explanation:

Complex Roots, Real Roots, and Imaginary Roots of an Equation

For the equation (x - 2)(x + 2)(x^2 + 4) = 0, we can determine the complex roots as well as the possible number of real and imaginary roots. This equation is a product of three factors: two of them linear, (x - 2) and (x + 2), and one quadratic, (x^2 + 4).

The linear factors each give one real root. The solutions for (x - 2) = 0 and (x + 2) = 0 are x = 2 and x = -2, respectively.

The quadratic factor (x^2 + 4) does not have real roots because the term +4 does not allow for x^2 to be negative to cancel it out, hence there are no x-values where (x^2 + 4) = 0. Therefore, we solve the quadratic equation using the formula for complex roots where a = 1, b = 0, and c = 4:

x = (-b ± √(b^2 - 4ac)) / (2a)

Substituting in the values gives us:

x = (± √(0 - 4 * 1 * 4)) / 2

x = (± √-16) / 2

x = ± 4i / 2

x = ± 2i

Therefore, the roots of (x^2 + 4) = 0 are 2i and -2i, which are imaginary roots.

Summarizing, the equation has a total of four roots: two real roots and two imaginary roots.

User Mustafa J
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