Solve ODE using method of integrating factors.

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SUMMARY

The discussion focuses on solving the ordinary differential equation (ODE) dy/dx = y + cos(x) - sin(x) using the method of integrating factors. The equation can be rewritten in the standard form dy/dx - y = cos(x) - sin(x), where r(x) = -1 and f(x) = cos(x) - sin(x). The solution involves identifying the integrating factor e^(-x) to simplify the equation and find the general solution.

PREREQUISITES
  • Understanding of ordinary differential equations (ODEs)
  • Familiarity with the method of integrating factors
  • Knowledge of functions and their derivatives
  • Basic trigonometric identities involving sine and cosine
NEXT STEPS
  • Study the method of integrating factors in detail
  • Practice solving first-order linear ODEs
  • Explore the use of integrating factors with non-homogeneous equations
  • Learn about exact differentials and their applications in ODEs
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Students studying differential equations, mathematics educators, and anyone looking to enhance their problem-solving skills in ODEs.

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Homework Statement


solve the following equation using method of intergrating factors:


Homework Equations


dy/dx = y + cosx - sinx


The Attempt at a Solution



i think i have to get it in the form dy/dx + r(x)y = f(x)

but i can't see how,

if i multiply or divide by a factor i won't have dy/dx on its own. and how do i identify what's f(x) and r(x)?

i also tried

dy + (-y -cosx +sinx)dx = 0

and then just finding a factor to make it an exact differential, but I am not sure how i determine the factor.
 
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simply subtract the y from both sides...
dy/dx -y = cosx - sinx

your function in front of y is simply a constant function (-1)
 
its kinda obvious that y=sin(x) is a solution...
 

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