The discriminant is an important concept in the context of quadratic equations, as it provides valuable information about the nature of the roots of the equation. For a standard quadratic equation in the form:
ax2 + bx + c = 0
the discriminant (denoted as D) is given by the formula:
D = b2 - 4ac
In your case, the quadratic equation is:
2x + 5x2 + 1 = 0
First, we need to rearrange this equation into the standard form:
5x2 + 2x + 1 = 0
Now, we can identify the coefficients:
- a = 5
- b = 2
- c = 1
Next, we can substitute these values into the formula for the discriminant:
D = (2)2 - 4(5)(1)
Calculating this gives:
D = 4 - 20
Therefore:
D = -16
The value of the discriminant tells us about the nature of the roots of the quadratic equation:
- If D > 0, the equation has two distinct real roots.
- If D = 0, the equation has exactly one real root (also called a repeated root).
- If D < 0, which is the case here, the equation has two complex (imaginary) roots.
Since the discriminant for the quadratic equation 5x2 + 2x + 1 is -16, we conclude that this quadratic equation has two complex roots.