# what is the C/D equation in dsp?

I have one example test question by this kind:

So in this ebook (Digital Signal Processing Using MATLAB) as the DSP references and not found C/D block equations on it?

and this c/d search results?

C/D is simply a "continuous-to-discrete" time conversion. In other words, sampling! :-) You can use $$T$$ to sample your continuous time signal $$x(t)$$ into a discrete time signal $$x[n]$$. Just replace $$t=nT$$ in your $$x(t)$$ equation, to turn it into a discrete time signal $$x[n]$$. D/C is the opposite operation. I think you can move on from here. Let us know if you can work it out now or if you need further help.