Question

what exactly means by d/dx ?

Answer 1

nothing, unless you mean dy/dx

Answer 2

okey, so, what does it means by dy/dx?

Answer 3

derivative, basically the instantaneous rate of change with respects to x at some x value

Answer 4

d/dx is an operator that indicates you want to take the derivative of some relation with respect to, well, x in this case since its a dx on the bottom

Answer 5

dy/dx is the operation that was done on the relationship of y with respect to x

Answer 6

Also, to speak of the instananouse rate of change of y with respect to x as some value of xsub 1 of x is lenghty. So we can this change of rate, the derivaitve (dy/dx) of y with respects to x and when necessary specify at xub1 or a specific value of x