solve the diffrential equation (x^4-2xy^2+y^4)dx-(2x^2y-4xy^3+ siny)dy =0
Answers
Answer:
x^5/5 -x^2y^2+xy^4-cosy+C
Step-by-step explanation:
This is homogenous equation in order to began to solve it you must do the exactness differential equation test
which is found in this image
https://www.google.com/url?sa=i&source=images&cd=&ved=2ahUKEwiN35Ko28zlAhWldN8KHRlBAFoQjRx6BAgBEAQ&url=https%3A%2F%2Fslideplayer.com%2Fslide%2F8582157%2F&psig=AOvVaw1PWg_oFy3iPTAdZBsKusYi&ust=1572824851286584
as you can see that M(x,y) represents the side of equation attached to dx
N(x,y) represents the side of equation attached to dy
dx represents the differentiation respect to x
dy represents the differentiation respect to y
so the function was having both x and y as variables
F(x,y)
we call it F
when you differentiate it you began to
dF=dF/dx +dF/dy
so the problem is how to return it back
the test can solve this problem as it was proven by mathematician
This test you can understand its concept even more by watching this video
https://www.youtube.com/watch?v=WgHCy25hBJE&t=829s
now to do you the test you began to differentiate the side attached to dx with respect to y so you treat x as a constant
4xy-4y^3
you diiferentiate side attached to dy with respect to x so you treat y as a constant
4xy-4y^3
they are the same so you begin to solve the problem
by integrating the side attached to dx with respect to x
x^5/5 -x^2y^2+xy^4+k(y)
this k represent function of y as you differentiated x you removed y as it wads constant with respect to x
this is F(x,y) so you have to diferentiate it with respect to y in order to find k(y)
2xy^2+4xy^3+k'(y)
you equal it with the side attached to dy in the main equation
you will find that
k'(y)=siny
by integration
so k(y)=--cosy+C
you subsitute it you will get the answer
Answer:
4-2xy^2+y^4)dx-(2x^2y-4xy^3+ siny)dy =0