What is the rate of change between the interval x = ? and x = 3pi/2?

Are you asking "what is the average rate of change of (the function) on the interval (x, 3pi/2)?"  You need to share the function in question, as well as to supply the value of x.  Please go back to the original question and ensure that you have copied it exactly as it was presented to you.  Again:  specify the function and indicate the value of x, which is the starting value of the interval in question.

Well what if i told you it wouldn’t matter, because in the future the pony dies, depending on what choice you make