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I am trying to replicate a solution in Matlab for the following problem ##\displaystyle \ddot x + \frac{k}{m}x = \frac{F_o}{m} \sin w_ot##

using 2 first order linear differential equations in Matlab as shown below

tspan=[0 4];

y0=[.02;1]; %Initial Conditions for y(1)=x and y(2)= x dot

[t,y]=ode45(@forced1,tspan,y0); %Calls forced1.m

plot(t,y(:,2)); %y(:,1) represents the displacement and y(:,2) the velocity

grid on

xlabel('time')

ylabel('Displacement')

title('Displacement Vs Time')

hold on;

function yp = forced1(t,y)

m=20;

k=800;

f=8;

w=8;

yp = [y(2);(((f/m)*sin(w*t))-((k/m)*y(1)))];

The problem is I dont know whether Matlab considers both the complementary and particular solution. THe theoretical solution is given as

##\displaystyle x=A \sin w_nt +B \cos w_nt+ \frac{\frac{F_o}{k}}{1-(\frac{w_o}{w_n})^2} \sin w_ot##

where the 3rd term is the particular solution assumed of the form ##x_p=C \sin w_o t##. I am not sure how to implement this correctly in Matlab

Any ideas?

Thanks

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# [MATLAB] Simple Undamped Forced Vibration Problem

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