Toronto Math Forum
MAT244-2013S => MAT244 Math--Tests => Final Exam => Topic started by: Victor Ivrii on April 17, 2013, 03:02:14 PM
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\begin{equation*}
y^{(4)} -3y''-4y = \sin (t)+8 t.
\end{equation*}
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solve homogeneous-> roots are i,-i,2,-2
Yh=c1 e^2t +c2 e^-2t +c3 cost +c4 sint
Yp-> undetermined coefficients-> Yp= Atcost +Btsint +Ct +D
evaulate polynomial terms => C=-2. D=0
evaulate sinusoidal terms => A=1/10 B=0
Y= c1 e^2t +c2 e^-2t +c3 cost +c4 sint + (1/10)tcost -2t
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Also, I MIGHT have used 'x' instead of 't' on the test, would I lose marks if I used the wrong variable?
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i did this
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Solutions
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Benny, WTH you posted Q1 into FE-3 and Q3 into FE-1 (so I needed to split and merge)?