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The coefficients b and c in the equation x²+bx+c = 0 are also the roots of that

equation (c #0). Find b and c.

1 Answer

5 votes

With b = -1 and c = 0 satisfies Vieta's formulas: the sum of the roots is -b, and the product of the roots is equal to the constant term. Here option C is correct.

Let's consider the quadratic equation x^2 + bx + c = 0 with roots b and c. According to Vieta's formulas:

The sum of the roots (b + c) is equal to the negation of the coefficient of x (with the opposite sign).

The product of the roots (bc) is equal to the constant term.

Now, let's analyze the options:

A) b = 1, c = 0

Sum of the roots: 1 + 0 = 1

Product of the roots: 1 * 0 = 0

The sum is not equal to -b, so this option is not correct.

B) b = 0, c = 1

Sum of the roots: 0 + 1 = 1

Product of the roots: 0 * 1 = 0

The sum is not equal to -b, so this option is not correct.

C) b = -1, c = 0

Sum of the roots: -1 + 0 = -1

Product of the roots: -1 * 0 = 0

The sum is equal to -b, so this option is correct.

D) b = 0, c = -1

Sum of the roots: 0 + (-1) = -1

Product of the roots: 0 * (-1) = 0

The sum is equal to -b, so this option is also correct.

Therefore, both options C and D satisfy the conditions, but only option C has c ≠ 0. Here option C is correct.

Complete question:

The coefficients b and c in the equation x^2 + bx + c = 0 are also the roots of the equation c doesnt equal o find b and c

A) b = 1, c = 0

B) b = 0, c = 1

C) b = -1, c = 0

D) b = 0, c = -1

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