Solve the equation x^2 - 5x + 10 = 0. Write your conjugate pair solution(s) as two values separated by a \pm sign.

1 answer

To solve the equation \( x^2 - 5x + 10 = 0 \), we can use the quadratic formula:

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

In our equation, the coefficients are:

  • \( a = 1 \)
  • \( b = -5 \)
  • \( c = 10 \)

Now, we first need to calculate the discriminant \( b^2 - 4ac \):

\[ b^2 - 4ac = (-5)^2 - 4 \cdot 1 \cdot 10 = 25 - 40 = -15 \]

Since the discriminant is negative, the solutions will be complex. Now, we apply the quadratic formula:

\[ x = \frac{-(-5) \pm \sqrt{-15}}{2 \cdot 1} \]

This simplifies to:

\[ x = \frac{5 \pm \sqrt{-15}}{2} \]

To express the square root of a negative number in terms of complex numbers, we write:

\[ \sqrt{-15} = i\sqrt{15} \]

Substituting this back into the equation gives:

\[ x = \frac{5 \pm i\sqrt{15}}{2} \]

Breaking this down, we can write:

\[ x = \frac{5}{2} \pm \frac{i\sqrt{15}}{2} \]

Thus, the solutions for the equation \( x^2 - 5x + 10 = 0 \) are

\[ \frac{5}{2} \pm \frac{i\sqrt{15}}{2} \]