Find the student's error in solving the following
inequality
31 < -5x + 6
25 < -5x
-5 the student should have added 6 to both
sides instead of subtracting it.
the student divided 251–5 incorrectly.
the student should have switched the
direction of the inequality sign to get -5> x for
a final answer.

Amass weighing 16 pounds stretches a spring 8/3 feet. the mass is initially released from rest from a point 2 feet below the equilibrium position, and the subsequent motion takes place in a medium that offers a damping force that is numerically equal to 1/2 the instantaneous velocity. find the equation of motion if the mass is driven by an external force equal to f(t)=cos(2t).