Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

In differential equations how do you know whether a differential equation is lin

ID: 3199118 • Letter: I

Question

In differential equations how do you know whether a differential equation is linear or nonlinear? Do you care only about the highest derivative of the dependent variable or do you also care if there is a dependent variable to a power?
How do you know the order of the differential equation? In differential equations how do you know whether a differential equation is linear or nonlinear? Do you care only about the highest derivative of the dependent variable or do you also care if there is a dependent variable to a power?
How do you know the order of the differential equation?
How do you know the order of the differential equation?

Explanation / Answer

Linear vs. Non-linear

An ODE for y = y(t) is linear if it can be written in the form

an(t) yn+ an-1(t) yn-1 + · · · + a3(t) y3 + a2(t) y'' + a1(t) y'+ a0(t) y = g(t)

where the ‘coefficient’ functions g(t), a0(t), ..., an(t) can be any functions of t, (including the zero function),

Example1. y''+ 2t3 y' = 5ty + t2 is a second order linear ODE, since it can be written

y''+ 2t3 y' + (-5ty) = t2

Ex2. y''= yy' ? 9 is a second order nonlinear ODE, due to the term yy'

Ex3. y2 + y' = ? t is a first order nonlinear ODE

Note- We care only power of dependent variable for example

y -> linear, y2 -> non linear

Order of differential Equation - Order of differential is the highest derivative of dependent variable

Example-y''+ 2t3 y' = 5ty + t2

It is 2nd order differential euation

Example- y2 + y' = ? t

It is a first order Differential equation

Hire Me For All Your Tutoring Needs
Integrity-first tutoring: clear explanations, guidance, and feedback.
Drop an Email at
drjack9650@gmail.com
Chat Now And Get Quote