Derivatives and Chain Rule: Solving for x and y

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annoymage
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Homework Statement



let x=et and define y(x(t))=Y(t)

Show that x(d/dx)y=(d/dt)Y

Homework Equations



n/a

The Attempt at a Solution



i try using chain rule but

x(dy/dt)(dt/dx) and i don't know how to make it to be dY/dt, and i don't have clue what is the point of x=et.. help T_T
 
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Look at it the other way around. If [itex]x= e^t[/itex] then [itex]dy/dt= (dy/dx)(dx/dt)= e^t(dy/dx)= x(dy/dx)[/itex]. The point of "[itex]x= e^t[/itex] is that the derivative of [itex]x= e^t[/itex] is [itex]x= e^t[/itex].
 


my goodness, thank you very very very much