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Find the Sum and product of the roots of the given equation.

1. 4x^2 - 3x + 9 = 0
2. 3x^3 + 5x^2 - x = 3
3. x^5 - 4x^3 = 6

User Nathaly
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1 Answer

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Final Answer:

1. The sum of the roots of the equation 4x² - 3x + 9 = 0 is
\( (3)/(4) \), and the product is
\( (9)/(4) \).

2. For the equation 3x³ + 5x² - x = 3, both the sum and product of the roots are complex.

3. The equation x⁵ - 4x³ = 6 has roots with a sum of 0 and a product of -6.

Step-by-step explanation:

In the first equation,
\(4x^2 - 3x + 9 = 0\), we can find the sum and product of the roots using Viète's formulas. For a quadratic equation
\(ax^2 + bx + c = 0\), the sum of the roots
(\(r₁\) and
\(r₂\)) is given by
\( (-b)/(a) \) and the product is
\( (c)/(a) )\. Applying this to the given equation, the sum is
\( (3)/(4) \) and the product is
\( (9)/(4) \).

Moving to the second equation
\(3x^3 + 5x^2 - x = 3\), the roots can be complex. Viète's formulas still apply, but now for a cubic equation
\(ax^3 + bx^2 + cx + d = 0\), the sum of the roots is
\( (-b)/(a) \) and the product is
\( (d)/(a) \). Here, we find both the sum and product to be complex.

For the third equation
\(x^5 - 4x^3 = 6\), it's interesting to note that the sum of the roots is 0, and the product is -6. Viète's formulas for a quintic equation
\(ax^5 + bx^4 + cx^3 + dx^2 + ex + f = 0\) yield the sum
\( (-b)/(a) \) and the product
\( (-f)/(a) \). In this case, the sum is 0, reflecting the symmetric nature of the roots, and the product is -6.

User Pablo Montilla
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