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Roots in Quadratic Equations

Learn About Finding Out Roots in Quadratic Equations, Roots of Quadratic Equation, Formula of Roots of Quadratic Equation, relation between Roots and Quadratic Equation and many things.

A quadratic issue is one in which a variable is multiplied by itself, a process known as squaring in mathematics.

In this language, the side length of a square is multiplied by itself to determine its size. The term “quadratic” is derived from the Latin quadratum, which means “square.”

Quadratic equations can be used to model a variety of real-life scenarios, such as where a rocket ship will land, how much to charge for a product, and how long it takes a person to paddle up and down a river. Because of their wide range of applications, quadratics have a lengthy history and are crucial to the history of algebra

What is the Quadratic Equation?

A second-degree algebraic equation in x is known as a quadratic equation. ax² + bx + c = 0 is the traditional form of the quadratic equation, with a and b as coefficients, x as the variable, and c as the constant component. The coefficient of x² is a non-zero term (a 0), which is the first criterion for determining if an equation is quadratic. The x² term occurs first in a quadratic equation written in standard form, followed by the x term, and finally the constant term. Integral values are typically employed to express the numeric values of a, b, and c rather than fractions or decimals.

Roots of Quadratic Equation

The roots of the quadratic equation ax² + bx + c = 0 are just the quadratic equation’s solutions. In other words, these are the variables’ (x) values that satisfy the equation. The roots of a quadratic function are the x-coordinates of the function’s x-intercepts. Because the degree of a quadratic equation is two, it can only have two roots. The roots of quadratic equations can be found using a variety of methods.

  • Factoring (when possible)
  • Quadratic Formula
  • Completing the Square
  • Making graphs (used to find only real roots)

Let us learn more about the roots of quadratic equations, including discriminant, nature of the roots, sum of roots, product of roots, and other concepts, as well as some instances.

Quadratic Equation Roots

Quadratic equations’ roots are the values of the variables that satisfy the equation. They’re also known as the quadratic equation’s “solutions” or “zeros.” Because they satisfy the equation, the roots of the quadratic equation x² – 7x + 10 = 0 are x = 2 and x = 5. i.e.,

  • when x = 2, 22 – 7(2) + 10 = 4 – 14 + 10 = 0.
  • when x = 5, 52 – 7(5) + 10 = 25 – 35 + 10 = 0.

But how do you find the roots of a quadratic equation like ax2 + bx + c = 0? Let’s see if we can fill up the square to solve for x.

ax² + bx = – c

Using the letter ‘a’ to divide both sides,

 + (b/a) x = – c/a

The coefficient of x is b/a in this case. Half of it is due to b/ (2a). b²/4a² is its square. On both sides, add b²/4a².

+ (b/a) x + b²/4a² = (b²/4a²) – (c/a)

[ x + (b/2a) ]

2 = (b2 – 4ac) / 4a²  (using the formula (a + b)²)

On both sides, take the square root.

x + (b/2a) = ±√ (b² – 4ac) / 4a²

x + (b/2a) = ±√ (b² – 4ac) / 2a

We get b/2a by removing both sides.

x = (-b/2a) ±√ (b² – 4ac) / 2a (or)

x = (-b ± √ (b² – 4ac) )/2a

This is referred to as the quadratic formula, and it may be used to find any sort of quadratic equation root.

How to Find the Roots of Quadratic Equations?

The technique of finding the roots of quadratic equations is known as “solving quadratic equations.” The quadratic formula, as seen in the preceding section, can be used to find the roots of a quadratic equation. In addition to this method, there are a few others for locating the roots of a quadratic equation. For a more in-depth look at these tactics, click here. Let’s take a closer look at each of these tactics by tackling a problem involving determining the roots of the quadratic equation x² – 7x + 10 = 0. (from the previous section). In each of these cases, the equation should be written as ax² + bx + c = 0.

Important Formulas for Quadratic Equation Roots include:

ax² + bx + c = 0 is a quadratic equation.

  • Use the formula x = (-b ± √ (b² – 4ac) )/2a. to calculate the roots.
  • D = b² – 4ac is the discriminant.

If D is greater than zero, the equation has two distinct and real roots.

When D is less than zero, the equation has two complex roots.

The equation has just one real root if D = 0.

  • -b/a is equal to the total of the roots.
  • The root product equals c/a

Conclusion:

The roots have physical relevance because the graph of an equation contacts the x-axis at the roots. In the Cartesian plane, the x-axis symbolizes the real line. Because unreal roots do not intersect the x-axis, an equation cannot be factored.

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Frequently Asked Questions

Get answers to the most common queries related to the CAT Examination Preparation.

What are the 4 methods in finding the roots of a quadratic equation?

Answer: The four methods for solving a quadratic equation are factoring, using square roots, completing the square, ...Read full

How do you find the number of roots?

Answer: You must compute the discriminant to determine the number of roots in a quadratic ax²...Read full

What is the use of the root of an equation?

Answer: We can figure out where the graph of a function intersects the x axis by identifying the roots of an equatio...Read full

What are some of the uses for quadratic functions?

Answer: Quadratic functions are used in a variety of scenarios in the real world. They can be used to describe the t...Read full

What do quadratic equations solve?

Answer: The quadratic formula is used in Example to solve an equation with non-rational roots.