(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

If [itex]z = f(x,y)[/itex] such that [itex]x = r + t[/itex] and [itex]y = e^{rt}[/itex], then determine [itex]\nabla f(r,t)[/itex]

2. Relevant equations

[itex]\nabla f(x,y) = <f_x,f_y>[/itex]

3. The attempt at a solution

Now if i follow this the way i think it should be done then i find the partials of f wrt x and y and then simply sub in r and t in the place of x and y respectively...

But if i get del f the normal way i get:

[itex]\nabla f = <f_x+f_y t e^{rt},f_x+f_y r e^{rt}>[/itex]

is this the final/correct answer or am i missing a trick question where i was asked to find del f(r,t) and not del f(x,y)

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# Gradient vector problem

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