How to Find the Equation for a Quadratic with a Root of 1 + 3i?

In summary, to find the equation for a quadratic equation with one root at 1+3i, the other root can be either its complex conjugate (1-3i) if real coefficients are required, or any complex number if not. The equation can be of the form a(x-1-3i)(x-1+3i)=0 with a being any number.
  • #1
suganya
4
0
Hi,

How to find the equation if one root of a quadratic equation is 1 + 3i.

Regards,
Suganya

EasyCalculation
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  • #2
Does the equation has real co efficients? If it does, the other root is the complex conjugate of that root. If not, and you have the co efficients which I don't think you do, then just set (x - your root) as a factor and divide. If you don't know any of that information, no way to tell.
 
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  • #3
Your "find the equation" implies that there is only one such equation. There isn't. If a quadratic equation has x0 and x1 as roots, then it must be of the form a(x-x0)(x- x1)= 0 where a can be any number.

You know that one root is 1+ 3i. As Gib Z said, if your equation must have real coefficients, then the other root must be its complex conjugate 1- 3i so any equation of the form a(x- 1- 3i)(x- 1+ 3i)= 0 will work. If you do not require real coefficients, choose any complex number at all for the second root!
 
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What is a Quadratic Equation?

A quadratic equation is a mathematical expression that includes a variable raised to the second power (x^2) and may also include a variable raised to the first power (x) and a constant term. It is typically written in the form ax^2 + bx + c = 0, where a, b, and c are constants and a cannot equal 0.

What is the importance of Quadratic Equations?

Quadratic equations are important in many fields, including mathematics, engineering, physics, and economics. They are used to model real-world phenomena, such as projectile motion, and to solve problems involving optimization and finding the roots of a function. They also provide a foundation for more complex forms of equations and functions.

How do you solve a Quadratic Equation?

There are several methods for solving a quadratic equation, including factoring, using the quadratic formula, and completing the square. The most common method is using the quadratic formula, which is: x = (-b ± √(b^2 - 4ac)) / 2a. This formula can be used to find the two possible solutions for a quadratic equation.

What is the discriminant of a Quadratic Equation?

The discriminant of a quadratic equation is the expression under the square root in the quadratic formula, b^2 - 4ac. It helps determine the nature of the solutions to the equation. If the discriminant is positive, there are two real solutions. If it is zero, there is one real solution. And if it is negative, there are no real solutions, but there may be two complex solutions.

What is the difference between a Quadratic Equation and a Linear Equation?

A linear equation is a mathematical expression that includes a variable raised to the first power (x) and a constant term. It is typically written in the form ax + b = 0, where a and b are constants and a cannot equal 0. A quadratic equation, on the other hand, includes a variable raised to the second power (x^2) and may also include a variable raised to the first power (x) and a constant term. It is typically written in the form ax^2 + bx + c = 0, where a, b, and c are constants and a cannot equal 0. The key difference is that a quadratic equation has a squared term, while a linear equation does not.

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