When a 7kg mass is attached to a spring whose constant is 112N/m, it comes to rest in the equilibrium position. Starting at t = 0, a force equal to f(t) = 35e2tcos4t is applied to the system. In the absence of damping,

(a) find the position of the mass when t = .

(b) what is the amplitude of vibrations after a very long time?

Problem #7: When a 7 kg mass is attached to a spring whose constant is 112 N/m, it comes to rest in the equilibrium position. Starting at I = 0, a force equal to f (I) = 35921: cos 4! is applied to the system. In the absence of damping, (a) nd the position of the mass when f= 7r. ('1) what is the amplitude of vibrations after a very long time? Problem #7(a): |:| Round your answer to 4 decimals. Problem #7(b): |:| Round your answer to 4 decimals