In[]:=
sol=NDSolve[​​{​​32f'[t]==Exp[Cos[t]-f[t]-f'[t]-f''[t]]-1​​,f[0]==0​​,f'[0]==0​​}​​,f​​,{t,0,64Pi}​​,Method->{​​"EquationSimplification"->"Residual"​​}​​];​​Plot[f[t]/.sol,{t,0,64Pi}]
Out[]=
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Plot[f[t]/.sol,{t,62Pi,64Pi}](*approximatesolutionforsteadystate*)
Out[]=
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