Author Topic: FE-1  (Read 1479 times)

Victor Ivrii

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FE-1
« on: April 17, 2013, 02:59:06 PM »
Find the general solution of the differential equation
\begin{equation*}
y' +y \tan x =\sin (x)
\end{equation*}
and solve the initial value problem $y(0) = 1$.
« Last Edit: April 17, 2013, 11:12:22 PM by Victor Ivrii »

Jason Hamilton

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Re: FE-1
« Reply #1 on: April 17, 2013, 04:22:46 PM »
find integrating factor: u=exp(integral tanxdx)=sec x


secx y= integral (tan x)= - ln (cosx) +C

y=-cosx(ln cosx) + C cosx

y(0)=1 => C=1

y=-cosx(ln cosx) + cosx

Victor Lam

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Re: FE-1
« Reply #2 on: April 17, 2013, 06:07:07 PM »
solution

Benny Ho

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Q1
« Reply #3 on: April 17, 2013, 09:18:39 PM »
Solution