Undergrad Chain rule in a multi-variable function

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To find the total derivative of a parameterized multi-variable function F[x(t), y(t), dot{x}(t), dot{y}(t)], the correct expression according to the chain rule includes contributions from all variables. The expression should be ##\frac{dF}{dt} = \frac{\partial F}{\partial x} \frac{dx}{dt} + \frac{\partial F}{\partial y} \frac{dy}{dt} + \frac{\partial F}{\partial \dot{x}} \frac{d\dot{x}}{dt} + \frac{\partial F}{\partial \dot{y}} \frac{d\dot{y}}{dt}##. Each term represents the rate of change of F with respect to each variable and their respective derivatives. This indicates that the total derivative must account for all parameters involved, including the derivatives of dot{x} and dot{y}. Understanding these components clarifies the application of the chain rule in multi-variable functions.
Ananthan9470
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Suppose you have a parameterized muli-varied function of the from ##F[x(t),y(t),\dot{x}(t),\dot{y}(t)]## and asked to find ##\frac{dF}{dt}##, is this the correct expression according to chain rule? I am confused because of the derivative terms involved.

##\frac{dF}{dt}=\frac{\partial F}{\partial x} \frac{dx}{dt} + \frac{\partial F}{\partial y} \frac{dy}{dt}##

Or similar terms containing ##\dot{x}(t)## etc should also be included or it is something else altogether?
 
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Ananthan9470 said:
Suppose you have a parameterized muli-varied function of the from ##F[x(t),y(t),\dot{x}(t),\dot{y}(t)]## and asked to find ##\frac{dF}{dt}##, is this the correct expression according to chain rule? I am confused because of the derivative terms involved.

##\frac{dF}{dt}=\frac{\partial F}{\partial x} \frac{dx}{dt} + \frac{\partial F}{\partial y} \frac{dy}{dt}##

Or similar terms containing ##\dot{x}(t)## etc should also be included or it is something else altogether?
If the function had parameters x, y, z, and w, the total derivative would have four terms, with the last two being ##\frac{\partial F}{\partial z} \frac{dz}{dt} + \frac{\partial F}{\partial w} \frac{dw}{dt}##. I believe that the derivative you're trying to find needs similar terms, with the partials being with respect to ##\dot{x}## and ##\dot{y}##.
 

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