Quadratic equations with complex roots

2010013201

Level: 
A
Find the complex roots of the following quadratic equation. \[ 3x^2 + 8 = 0 \]
\( x_1=-\frac{2\sqrt{6}}3\mathrm{i},\ x_2=\frac{2\sqrt{6}}3\mathrm{i} \)
\( x_1=-\frac{\sqrt{6}}3\mathrm{i},\ x_2=\frac{\sqrt{6}}3\mathrm{i} \)
\( x_1=-\frac{\sqrt{12}}3\mathrm{i},\ x_2=\frac{\sqrt{12}}3\mathrm{i} \)
\( x_1=-\frac{\sqrt{6}}6\mathrm{i},\ x_2=\frac{\sqrt{6}}6\mathrm{i} \)

9000035603

Level: 
A
Find the solution set of the following equation. \[ 4x^{2} + 9 = 0 \]
\(\left \{-\frac{3} {2}\mathrm{i}; \frac{3} {2}\mathrm{i}\right \}\)
\(\left \{-\frac{2} {3}\mathrm{i}; \frac{2} {3}\mathrm{i}\right \}\)
\(\left \{-\frac{9} {4}\mathrm{i}; \frac{9} {4}\mathrm{i}\right \}\)
\(\left \{-\frac{3} {2}; \frac{3} {2}\right \}\)

9000064505

Level: 
A
Find the factorization of the following quadratic polynomial in the set of polynomial with complex valued coefficients. \[ 2x^{2} + 32 \]
\(2(x + 4\mathrm{i})(x - 4\mathrm{i})\)
\(2(x - 4\mathrm{i})^{2}\)
\((x + 4\mathrm{i})(x - 4\mathrm{i})\)
\(2(x + 4\mathrm{i})^{2}\)

9000064506

Level: 
A
Find the factorization of the following quadratic polynomial in the set of polynomial with complex valued coefficients. \[ 2x^{2} + 4x + 5 \]
\(2\! \left (x + 1 + \frac{\sqrt{6}} {2} \mathrm{i}\right )\! \! \left (x + 1 -\frac{\sqrt{6}} {2} \mathrm{i}\right )\)
\(2\! \left (x - 1 + \frac{\sqrt{6}} {2} \mathrm{i}\right )\! \! \left (x - 1 -\frac{\sqrt{6}} {2} \mathrm{i}\right )\)
\(\left (x + 1 -\frac{\sqrt{6}} {2} \mathrm{i}\right )\! \! \left (x + 1 + \frac{\sqrt{6}} {2} \mathrm{i}\right )\)
\(\left (x - 1 -\frac{\sqrt{6}} {2} \mathrm{i}\right )\! \! \left (x - 1 + \frac{\sqrt{6}} {2} \mathrm{i}\right )\)

9000064508

Level: 
A
Solve the following quadratic equation in the complex plane. \[ 2x^{2} + x + 1 = 0 \]
\(x_{1, 2} = \frac{-1\pm \mathrm{i}\sqrt{7}} {4} \)
\(x_{1, 2} = \frac{-1\pm \mathrm{i}\sqrt{7}} {2} \)
\(x_{1, 2} = \frac{1\pm \mathrm{i}\sqrt{7}} {4} \)
\(x_{1, 2} = \frac{1\pm \mathrm{i}\sqrt{7}} {2} \)

9000069902

Level: 
A
Solve the following quadratic equation in the complex plane. \[ 3x^{2} + 2x + 2 = 0 \]
\(x_{1} = -\frac{1} {3} + \frac{\sqrt{5}} {3} \mathrm{i}\), \(x_{2} = -\frac{1} {3} -\frac{\sqrt{5}} {3} \mathrm{i}\)
\(x_{1} = -\frac{1} {3}\)
\(x_{1} = \frac{1} {3} + \frac{\sqrt{5}} {3} \), \(x_{2} = \frac{1} {3} + \frac{\sqrt{5}} {3} \)
\(x_{1} = \frac{1} {3} + \frac{\sqrt{5}} {3} \mathrm{i}\), \(x_{2} = \frac{1} {3} -\frac{\sqrt{5}} {3} \mathrm{i}\)

9000069903

Level: 
A
Find the factorization of the quadratic polynomial \[ x^{2} + 2x + 2 \] in the set of polynomials with complex valued coefficients.
\((x + 1 + \mathrm{i})(x + 1 -\mathrm{i})\)
\((x - 1 + \mathrm{i})(x - 1 -\mathrm{i})\)
\((x -\mathrm{i})(x + \mathrm{i})\)
\((x - 1 + \mathrm{i})(x + 1 -\mathrm{i})\)