DEQ/Algebra Question Solve for t

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Solved: DEQ/Algebra Question Solve for t

Homework Statement


Greetings,

I am having difficulty solving for t in the equation below. It is part of a DEQ question that asks at which time t does damped oscillation amplitude fall below a certain value. The relevant equation is below. My main problem is that I am having difficulty solving for t since t is a product of e and the sin function.


Homework Equations


<br /> \frac{\sqrt{31}}{150}=e^{-2t}\sin(2\sqrt{31}t)<br />


The Attempt at a Solution


Trying to take ln of both sides produces the following, which I am still at a loss as how to solve for t.
<br /> \ln{\frac{\sqrt{31}}{150}}=-2t+\ln(\sin(2\sqrt{31}t))<br />

Any help is greatly appreciated.
 
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Fish Sauce said:

Homework Statement


Greetings,

I am having difficulty solving for t in the equation below. It is part of a DEQ question that asks at which time t does damped oscillation amplitude fall below a certain value. The relevant equation is below. My main problem is that I am having difficulty solving for t since t is a product of e and the sin function.


Homework Equations


<br /> \frac{\sqrt{31}}{150}=e^{-2t}\sin(2\sqrt{31}t)<br />

The only way to solve that for t would be numerically.
 
LCKurtz said:
The only way to solve that for t would be numerically.

Thank you LCKurtz.

I thought I was overlooking a simple algebraic solution and was losing hair over this!

Thanks again!
 
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