How to write the Laplace symbol s in trigonometric function?

Hi,

I am trying to express a transfer function, which has the Laplace symbol s in a sine function. I am wondering how to express this in Matlab? The transfer function is:

I wrote is as

ms=(3.77-0.034)/2.5e-6; K1=sin(s*Toff/(2i))*asin(s*(Ton+Toff)/(2i))*(Ton+Toff)/Toff;

Fm=Toff/(ms*(Ton+Toff)^2)*K1*exp(s*Ton/2);

However, Matlab can not recognize this code.

Please help me with this question.

Answer 1

[Walter Roberson]

If you have the symbolic toolbox then proceed those lines with

syms s

[Siyu He]

Thanks Walter.

I have the symbolic toolbox, but I need this transfer function to be plotted by command bode(); Can I still use the syms s?