Sunday, August 7, 2022

What Are Roots In Algebra

Don't Miss

Roots Of Quadratic Functions

Understanding square roots | Pre-Algebra | Khan Academy

We have already learned to solve for x in ax2 + bx + c = 0 by factoring ax2 + bx + c and using the zero product property. Since the roots of a function are the points at which y = 0, we can find the roots of y = ax2 + bx + c = 0 by factoring ax2 + bx + c = 0 and solving for x. We can also find the roots of y = ax2 + bx + c = 0 using the quadratic formula, and we can find the number of roots using the discriminant.

If a quadratic function has 2 roots–i.e., if it can be factored into 2 distinct binomials or if b2 -4ac> 0–then it crosses the x-axis twice. Either the vertex is below the x-axis and the leading coefficient is positive, or the vertex is above the x-axis and the leading coefficient is negative.

If a quadratic function has 1 root –i.e. if it can be factored as the square of a single binomial or if b2 – 4ac = 0–then it crosses the x-axis once. The vertex lies on the x-axis, and the leading coefficient can be positive or negative.

If a quadratic function has no roots–i.e. if it cannot be factored or if b2 -4ac< 0–then it does not cross the x-axis. Either the vertex is above the x-axis and the leading coefficient is positive, or the vertex is below the x-axis and the leading coefficient is negative. The quadratic equation is said to have 2 imaginary roots.

What Is A Radical In Math


A radical in math is the symbol \, which is used to represent a root. If there is no index , then it is assumed to be a square root. To represent the expression square root of \, we place the \ under the radical like so: \. A square root is a number that when multiplied by itself will produce the original number under the radical. Therefore, the square root of \ is equal to \ because \. This can also be written as \.


How To Find The Roots Of Quadratic Equation

The process of finding the roots of the quadratic equations is known as “solving quadratic equations”. In the previous section, we have seen that the roots of a quadratic equation can be found using the quadratic formula. Along with this method, we have several other methods to find the roots of a quadratic equation. To know about these methods in detail, click here. Let us discuss each of these methods here by solving an example of finding the roots of quadratic equation x2 – 7x + 10 = 0 in each case. Note that In each of these methods, the equation should be in the standard form ax2 + bx + c = 0.

Recommended Reading: Afda Mean Median Mode Range Practice

Square Roots Of Matrices And Operators

If A is a positive-definite matrix or operator, then there exists precisely one positive definite matrix or operator B with B2 = A we then define A1/2 = B. In general matrices may have multiple square roots or even an infinitude of them. For example, the 2 × 2identity matrix has an infinity of square roots, though only one of them is positive definite.

What Is The Index And Radicand

Understanding Square Roots


The index is the root that we are trying to find, and the radicand is the number under the radical symbol.

For example, \ is the square root of \. There is an imaginary \ that we do not write, which tells us that we should be taking the square root of the number. In this case, \ is the index and \ is the radicand. The expression, \, is the cube root of \. The \ is the index, the \ is the radicand, and the square root symbol is called the radical.

The index tells us which root of the radicand we are supposed to find. In the square root of \ case, we are finding a number that is multiplied by itself twice to get \. In the cube root of \, we are looking for a number that is multiplied by itself three times to get \.


Also Check: Beth Thomas Brother Jonathan Now

As Expansions In Other Numeral Systems

As with before, the square roots of the perfect squares are integers. In all other cases, the square roots of positive integers are irrational numbers, and therefore have non-repeating digits in any standard positional notation system.

The square roots of small integers are used in both the SHA-1 and SHA-2 hash function designs to provide nothing up my sleeve numbers.

Explicit Construction Of The Irreducible Root Systems


Let E be the subspace of Rn+1 for which the coordinates sum to 0, and let be the set of vectors in E of length 2 and which are integer vectors, i.e. have integer coordinates in Rn+1. Such a vector must have all but two coordinates equal to 0, one coordinate equal to 1, and one equal to 1, so there are n2 + n roots in all. One choice of simple roots expressed in the standard basis is: i = ei ei+1, for 1 i n.

The reflectioni through the hyperplane perpendicular to i is the same as permutation of the adjacent i-th and -th coordinates. Such transpositions generate the full permutation group.For adjacent simple roots, i = i+1 + i = i+1 = i + i+1, that is, reflection is equivalent to adding a multiple of 1 butreflection of a simple root perpendicular to a nonadjacent simple root leaves it unchanged, differing by a multiple of 0.

The An root lattice that is, the lattice generated by the An roots is most easily described as the set of integer vectors in Rn+1 whose components sum to zero.

The A2 root lattice is the vertex arrangement of the triangular tiling.

The A3 root lattice is known to crystallographers as the face-centered cubic lattice. It is the vertex arrangement of the tetrahedral-octahedral honeycomb.

The A3 root system may be modeled in the Zometool Construction set.

In general, the An root lattice is the vertex arrangement of the n-dimensional simplectic honeycomb.

0 1
0 2
1 1

You May Like: Rationalizing Imaginary Denominators Worksheet Answers

In Integral Domains Including Fields

Each element of an integral domain has no more than 2 square roots. The difference of two squares identity u2 v2 = is proved using the commutativity of multiplication. If u and v are square roots of the same element, then u2 v2 = 0. Because there are no zero divisors this implies u = v or u + v = 0, where the latter means that two roots are additive inverses of each other. In other words if an element a square root u of an element a exists, then the only square roots of a are u and u. The only square root of 0 in an integral domain is 0 itself.

In a field of characteristic 2, an element either has one square root or does not have any at all, because each element is its own additive inverse, so that u = u. If the field is finite of characteristic 2 then every element has a unique square root. In a field of any other characteristic, any non-zero element either has two square roots, as explained above, or does not have any.

Given an odd prime numberp, let q = pe for some positive integer e. A non-zero element of the field Fq with q elements is a quadratic residue if it has a square root in Fq. Otherwise, it is a quadratic non-residue. There are /2 quadratic residues and /2 quadratic non-residues zero is not counted in either class. The quadratic residues form a group under multiplication. The properties of quadratic residues are widely used in number theory.

Sum And Product Of Roots Of Quadratic Equation

Square Roots , Intermediate Algebra , Lesson 10

We have seen that the roots of the quadratic equation x2 – 7x + 10 = 0 are x = 2 and x = 5. So the sum of its roots = 2 + 5 = 7 and the product of its roots = 2 × 5 = 10. But the sum and the product of roots of a quadratic equation ax2 + bx + c = 0 can be found without actually calculating the roots. Let us see how.

We know that the roots of the quadratic equation ax2 + bx + c = 0 by quadratic formula are )/2a and )/2a. Let us represent these by x and x respectively.

Don’t Miss: Math Nation Independent Practice Answer Key

Principal Square Root Of A Complex Number


To find a definition for the square root that allows us to consistently choose a single value, called the principal value, we start by observing that any complex number x

. -x.}

AbelRuffini theorem states that, in general, the roots of a polynomial of degree five or higher cannot be expressed in terms of nth roots.

Root Systems And Lie Theory

Irreducible root systems classify a number of related objects in Lie theory, notably the following:

In each case, the roots are non-zero weights of the adjoint representation.

We now give a brief indication of how irreducible root systems classify simple Lie algebras over C } , following the arguments in Humphreys. A preliminary result says that a semisimple Lie algebra is simple if and only if the associated root system is irreducible. We thus restrict attention to irreducible root systems and simple Lie algebras.

For connections between the exceptional root systems and their Lie groups and Lie algebras see E8, E7, E6, F4, and G2.

Recommended Reading: Movement In Geography Examples

Square Roots Of Positive Integers

A positive number has two square roots, one positive, and one negative, which are opposite to each other. When talking of the square root of a positive integer, it is usually the positive square root that is meant.

The square roots of an integer are algebraic integersmore specifically quadratic integers.

The square root of a positive integer is the product of the roots of its prime factors, because the square root of a product is the product of the square roots of the factors. Since p

k . ^+1}\cdots p_^+1}p_^}\dots p_^}}}=p_^}\dots p_^}\dots p_}}.}

Working With Roots In Algebra

square roots/estimating square roots

There may be 0, 1 or 2 roots for a quadratic. A root is found for `x` when `f=0`. This can be seen graphically when the curve crosses `y=0`. If the curve does not cross `y=0` then there are no real roots for the function.

The roots can be obtained by:

⢠rearranging as factors

⢠using the quadratic formula `x = frac)`

⢠completing the square

⢠deducing iteratively

⢠and for an approximate solution: drawing a graph of the function.

Read Also: Cryptic Quiz Page 148 Answers

Nature Of Roots Of Quadratic Equation

The nature of the roots of a quadratic equation talks about “how many roots the equation has?” and “what type of roots the equation has?”. A quadratic equation can have:

  • two real and different roots
  • two complex roots
  • two real and equal roots

For example, in the above example, the roots of the quadratic equation x2 – 7x + 10 = 0 are x = 2 and x = 5, where both 2 and 5 are two different real numbers. and so we can say that the equation has two real and different roots. But for finding the nature of the roots, we don’t actually need to solve the equation. We can determine the nature of the roots by using the discriminant. The discriminant of the quadratic equation ax2 + bx + c = 0 is D = b2 – 4ac.

The quadratic formula is x = )/2a. So this can be written as x = /2a. Since the discriminant D is in the square root, we can determine the nature of the roots depending on whether D is positive, negative, or zero.

Example Corrected: What Is 2


When we square a negative number we get a positive result.

Just the same as when we square a positive number:

Now remember our definition of a square root?

A square root of x is a number r whose square is x:

r2 = xr is a square root of x

And we just found that:

2 = 25

So both +5 and 5 are square roots of 25

Read Also: Meaning Of Multiples In Math

Simplify Expressions With Higher Roots

Up to now, in this chapter we have worked with squares and square roots. We will now extend our work to include higher powers and higher roots.

Lets review some vocabulary first.

The terms squared and cubed come from the formulas for area of a square and volume of a cube.

It will be helpful to have a table of the powers of the integers from

Notice the signs in . All powers of positive numbers are positive, of course. But when we have a negative number, the even powers are positive and the odd powers are negative. Well copy the row with the powers of below to help you see this.

Earlier in this chapter we defined the square root of a number.

And we have used the notation to denote the principal square root. So always.

We will now extend the definition to higher roots.


not real

When we worked with square roots that had variables in the radicand, we restricted the variables to non-negative values. Now we will remove this restriction.

The odd root of a number can be either positive or negative. We have seen that .

But the even root of a non-negative number is always non-negative, because we take the principal nth root.

Suppose we start with

How can we make sure the fourth root of 5 raised to the fourth power, is 5? We will see in the following property.

For any integer ,

We must use the absolute value signs when we take an even root of an expression with a variable in the radical.


What Is The Easiest Way To Find Cube Roots

Radical expressions with higher roots | Algebra I | Khan Academy


The cube root of a number is a number that is multiplied by itself \ times to give the original number. The easiest way to find the cube root of a number is to start by finding the factors and see if there are \ numbers in the factor that are the same. For example, to find the cube root of \, we will start by finding the factors, which are \. Since \ is being multiplied by itself three times to produce \, we can say that \ is the cube root of \.


Read Also: How Did The Geography Of Greece Influence Greeks’ Interactions With Each Other

What Do You Mean By Nature Of Roots

An equation of the form \, where \ is called a quadratic equation.

The standard form of a quadratic equation looks like this:

This is a quadratic equation in variable \.

But always remember that \ is a non-zero value.

Now, to find the nature of the roots of the quadratic equation, we will first calculate the roots of the equation.

Nature of roots specifies that the equation has real roots, irrational roots, or imaginary roots.

Imaginary roots are also known as unreal roots.

Roots Of Polynomials Formula

The polynomials are the expression written in the form of:anxn+an-1xn-1++a1x+a0

The formula for the root of linear polynomial such as ax + b is

x = -b/a

The general form of a quadratic polynomial is ax2 + bx + c and if we equate this expression to zero, we get a quadratic equation, i.e. ax2 + bx + c = 0.

The roots of quadratic equation, whose degree is two, such as ax2 + bx + c = 0 are evaluated using the formula

x = /2a

The formulas for higher degree polynomials are a bit complicated.

Read Also: Paris Michael Katherine Jackson Real Father

Positive Roots And Simple Roots

we can always choose a set of positive roots. This is a subset

  • exactly one of the roots
  • } such that } .

If a set of positive roots + } are called negative roots. A set of positive roots may be constructed by choosing a hyperplane V not containing any root and setting to be all the roots lying on a fixed side of V . Furthermore, every set of positive roots arises in this way.

An element of + } is called a simple root if it cannot be written as the sum of two elements of . (The set of simple roots is also referred to as a base for of simple roots is a basis of E with the following additional special properties:

  • Every root is a linear combination of elements of
  • , the coefficients in the previous point are either all non-negative or all non-positive.

For each root system there are many different choices of the set of positive rootsor, equivalently, of the simple rootsbut any two sets of positive roots differ by the action of the Weyl group.

Properties Of The Irreducible Root Systems

Square Roots of Non

Irreducible root systems are named according to their corresponding connected Dynkin diagrams. There are four infinite families and five exceptional cases . The subscript indicates the rank of the root system.

In an irreducible root system there can be at most two values for the length 1/2, corresponding to short and long roots. If all roots have the same length they are taken to be long by definition and the root system is said to be simply laced this occurs in the cases A, D and E. Any two roots of the same length lie in the same orbit of the Weyl group. In the non-simply laced cases B, C, G and F, the root lattice is spanned by the short roots and the long roots span a sublattice, invariant under the Weyl group, equal to r2/2 times the coroot lattice, where r is the length of a long root.

In the adjacent table, |< | denotes the number of short roots, I denotes the index in the root lattice of the sublattice generated by long roots, D denotes the determinant of the Cartan matrix, and |W| denotes the order of the Weyl group.

Read Also: Ccl4 Dot Structure

More articles

Popular Articles