# What is the auxiliary equation of a differential equation?

## What is the auxiliary equation of a differential equation?

Equation 6 is called the auxiliary equation (or characteristic equation) of the differen- tial equation . Notice that it is an algebraic equation that is obtained from the differential equation by replacing by , by , and by . Sometimes the roots and of the auxiliary equation can be found by factoring.

### What is the roots of auxiliary equation?

Thus if a root of the auxiliary equation is r1 = α + iβ, then a solution is eα+iβ = eα(cos β + i sin β). Lemma 2. Let z(t) = u(t) + iv(t) be a solution to (1), where a, b, c ∈ R. Then, the real part u(t) and the imaginary part v(t) are real-valued functions of (1).

#### What is auxiliary equation in pair of straight lines?

It is in the form ax2 + 2hxy + by2 = 0.

What is meant by auxiliary equation?

: an equation obtained from the standard form of a linear differential equation by replacing the right member by zero.

What is auxiliary equation in maths?

## What is the significance of auxiliary equation?

Also called auxiliary equation. an equation with one variable and equated to zero, which is derived from a given linear differential equation and in which the coefficient and power of the variable in each term correspond to the coefficient and order of a derivative in the original equation.

### How do you find the roots of a differential equation?

Its roots are r1=43 r 1 = 4 3 and r2=−2 r 2 = − 2 and so the general solution and its derivative is. Now, plug in the initial conditions to get the following system of equations. Solving this system gives c1=−9 c 1 = − 9 and c2=3 c 2 = 3 . The actual solution to the differential equation is then.

#### How do you find the equation of a line from a pair of straight lines?

Therefore, to find the equation of a pair of straight lines, we multiply the equations of L1 and L2, i.e., (ax1+ by1 +c) * (ax2 + by2 + c) = 0.

What is meant by reciprocal equation?

If an equation is unaltered by changing x to x1 , it is called a reciprocal equation.

What is meant by characteristic equation?

The characteristic equation is the equation which is solved to find a matrix’s eigenvalues, also called the characteristic polynomial. For a general matrix , the characteristic equation in variable is defined by. (1) where is the identity matrix and is the determinant of the matrix .

## What do you need to know about the auxiliary equation?

1 auxiliary equation Definition. Auxiliary equation is the characteristic polynomial equation obtained from the homogenous linear differential equation by substitution, the roots of which determine the nature of the general solution 2 Overview of Auxiliary Equation. 3 Concept. 4 Auxiliary equation and nature of general solution.

### What is the solution of the auxiliary equation of the Ode?

It is also called the auxiliary equation of the ODE. The solution of λ in this case is simply (12.23)λ = − b ± √b2 − 4c 2. For simplicity, we can take A = 1 as it does not affect the results. From quadratic equations, we know that there are three possibilities for λ.

#### Can a complementary function satisfy the original equation?

Obviously, the complementary function yc alone cannot satisfy the original equation (12.16) because there is no way to produce the required f(x) on the right-hand side. Therefore, we have to find a specific function, y ⁎ (x) called the particular integral, so that it indeed satisfies the original equation (12.16). The combined general solution