Find Why K is Always Bigger than 1 for e^-t/k * sin2t

[Procrastinate]

I have a function that states:

$$e^{\frac{-t}{k}}\sin2t$$.

With the restriction k>1. There shouldn't be a dot next to the t.

I am meant to figure out why k is always bigger than one but so far, I am hatting a brick wall. Obviously, zero doesn't work because it yields a math error but the other decimals such as 0.9 or 0.8 can be graphed perfectly.

Could someone please give me any hints? I am thinking it might have something to do with time now but I am still blank.

 

[Tedjn]

You can graph them, but maybe there is some other reason why k is restricted to > 1? Maybe a physical reason? What is the context?

 

[Procrastinate]

It's related to harmonic motion (that is the actual context). I was thinking that perhaps it has something to do with a physical aspect. However, the harmonic motion equation (simple) is slightly different to this, so I didn't really pursue the idea further.