Solve the quadratic equation 10x^2-2x+13=3. Which of the following expresses its solutions in the form a± bi ? (1 point) 1/10 ± 3sqrt(11)/10 i 1/10 ± sqrt(101)/10 i 1/5 ± 3sqrt(11)/5 i _ frac 1+frac 3sqrt(11)i

1 answer

To solve the quadratic equation \( 10x^2 - 2x + 13 = 3 \), we first rearrange it into standard form:

\[ 10x^2 - 2x + 13 - 3 = 0 \]

This simplifies to:

\[ 10x^2 - 2x + 10 = 0 \]

Next, we will use the quadratic formula:

\[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \]

Here, \( a = 10 \), \( b = -2 \), and \( c = 10 \).

Now, calculate the discriminant \( b^2 - 4ac \):

\[ b^2 = (-2)^2 = 4 \] \[ 4ac = 4 \cdot 10 \cdot 10 = 400 \] \[ b^2 - 4ac = 4 - 400 = -396 \]

Since the discriminant is negative, we will have complex solutions.

Now substituting these values into the quadratic formula:

\[ x = \frac{-(-2) \pm \sqrt{-396}}{2 \cdot 10} = \frac{2 \pm \sqrt{-396}}{20} \]

Simplifying \( \sqrt{-396} \):

\[ \sqrt{-396} = \sqrt{396} i \]

Now we factor \( 396 \):

\[ 396 = 4 \cdot 99 = 4 \cdot 9 \cdot 11 = 36 \cdot 11 \]

Thus, \( \sqrt{396} = 6\sqrt{11} \):

\[ \sqrt{-396} = 6\sqrt{11} i \]

Therefore, substituting this back into the formula gives:

\[ x = \frac{2 \pm 6\sqrt{11}i}{20} \]

This simplifies as follows:

\[ x = \frac{2}{20} \pm \frac{6\sqrt{11}}{20}i = \frac{1}{10} \pm \frac{3\sqrt{11}}{10} i \]

Thus, the solutions to the quadratic equation \( 10x^2 - 2x + 13 = 3 \) in the form \( a \pm bi \) are:

\[ \frac{1}{10} \pm \frac{3\sqrt{11}}{10} i \]

So, the correct answer is:

\[ \frac{1}{10} \pm \frac{3\sqrt{11}}{10} i \]