Question about time dependence functions

kind of dumb question.
anyway, if we have a variable X which is function of time and another variable y which is also a function of time, does that mean that x is function of y?
i.e. if Z=∫xdy can i say Z=x*y or what.
actually this is kind of tricky as if this is wrong then any two unrelated variables can be assumed dependent, like if we say that the temp. on the sun has a certain function in time and the number of users that are registering on edaboard.com is also function of time then they are somehow dependent.

Re: time dependence

There is nothing wrong if such a kind of relationship is established between two seemingly unrealted variables. Now for example lets trace out motion of a particle α with respect to time, let the variable Y denote its displacement and t denote the time, in a Y-t plane satisfying the equation Y = b cosωt.

Now similarly lets trace out motion of a particle β with respect to time, let the variable X denote its displacement and t denote the time, in a X-t plane satisfying the equation X = a sinωt. Assuming that, the particles α and β start their motion simulatenously, we want to trace the displacement of the particle β w.r.t α now we have to find a relation ship between X and Y, eliminating t is simple in this case we get X²/a² + Y²/b² = 1 in the X-Y plane. So we can correlate motion of one with the other.

Now relating temperature of sun wrt number of members in EDA board well that will be an interesting equation to learn...

~Kalyan.

Re: time dependence

can u produce the dependence equation for sun and edaboard members...