Need Help Solving Initial Value Differential Equation

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SUMMARY

The discussion focuses on solving the initial value differential equation dy/dx + y*cos(x) = 3*cos(x) with the initial condition y(0)=5. The user attempted to find the particular solution using an integrating factor, m(t) = e^sin(x), and derived the equation y = (3(e^sin(x) + C))/(e^sin(x)). However, the user encountered an error while calculating the constant C, leading to an incorrect solution. The correct approach involves accurately determining the constant using the initial condition and ensuring proper algebraic manipulation.

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Homework Statement



dy/dx + y*cos(x) = 3*cos(x) . Find the particular solution of the differential equation dy/dx + y*cos(x) = 3*cos(x) satisfying the initial condition y(0)=5.

y(x) = ________________________



Homework Equations





The Attempt at a Solution



I thought I had done it the right way, but my computer based homework system disagreed.
Heres my work:

p(t)=cos(x)
g(t)=3cos(x)

m: mu

m(t)=exp [int] cos(x)dx
m(t)= e^sin(x)


then,

e^sinx(y)= [int]3cosx(e^sinx)dx

[int]3cosx(e^sinx)dx= 3(e^sinx)+C


then to solve for y,
y= 3(e^sin(x)+C)/(e^sin(x))

using the intial value to solve for C, [[the initial value was y(0)=5]]
5=3(e+C)/e
5e=3e + C<<<right here is it C or 3c?>>
c=2e

and plugging it back into the y-equation, I get y=(3(e^sinx)+2e)/(e^sinx)

Where have I gone wrong? My homework system says this is wrong... Any help would be greatly appreciated. Thank you for looking.
 
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sin(0)=0 and e^(0)=1 not e.
 

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