Engineering Is My Critically Damped RLC Circuit Formula Correct?

[gfd43tg]

Hello, I am working on this problem

However, I am getting a 900t term that the solution is lacking. I am wondering if what I did was wrong. My formula is consistent with the formula for a series RLC circuit that is critically damped.

 

[gneill]

Check: What is the sign of dV_C/dt at time t = 0+ ? Hint: In which direction is the initial current flowing?

 

[gfd43tg]

oh, I see. Thanks!