레이블이 differential equation인 게시물을 표시합니다. 모든 게시물 표시
레이블이 differential equation인 게시물을 표시합니다. 모든 게시물 표시

2016년 5월 23일 월요일

1st order ODE





Before you see this post,

see

e ( mathematical constant )


Relationship between Integral and Differential


Exact Differential Equation









There is a formula of ODE like former.

We can express the formula like latter.






We can consider 2 conditions.

First, the formula is non-exact differential equation.

Second, it is exact differential equation.

If it's non-exact differential equation, we can put F(x,y) and multiply with it. 





Let's suppose F(x,y) = F(x) , x dependent function.

We can find what function y is.







2016년 4월 25일 월요일

2016년 4월 23일 토요일

Introduction to Differential Equation



Differential Equations


1. Type

Ordinary Differential Equations


ex ) y" + y' = 0 , y" + 7 x( y' ) ^3 = 3x , ...


Partial Differential Equations


ex )
, ...






2. Linearity

Linear Differential Equations 


ex) y" + xy' = 7x,  8y"' + 3y' = xy, ...

Nonlinear Differential Equations


ex) (y"")^19 + (y")^ 30 - xy = 30x, ...







3. Order

1st, 2nd, 3rd, ... , n-th Order Differential Equations

ex)

y' + y^3 = 0 -> 1st order differential equation

(x^50)y" + (y')^300 + y = x -> 2nd order differential equation

x(y"')^20 + y = 3x^398 -> 3rd order differential equation