(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Find U(x,t)

dU/dt = d2U/dx2 + sin x

Boundary Conditions:

dU/dx (0,t) = 0

and

U(1,t) = 0

Initial Condition: U(x,0) = cos 7*π*x

2. The attempt at a solution

I start off with:

d2(Un)/dx2 = λnUn (as an initial value problem)

[d(Un)/dx](0) = 0; [d(Un)/dx](1) = 0

My teacher told me to use the orthogonality later on, but at this point I'm stuck.

Can anyone enlighten me? Thanks!

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# Homework Help: Non-Homogeneous Heat Equation (Insulated Bar Question)

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