Is the Multivariate Chain Rule Being Applied Correctly?

Kreizhn
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Homework Statement


Find
\frac{\partial z}{\partial y} [/itex]<br /> where z=F(u,v,y), u=f(v,x), v=g(x,y).<br /> <br /> <h2>The Attempt at a Solution</h2><br /> If I remember multivariate calculus at all, this should be (please forgive the abuse of notation)<br /> <br /> \frac{\partial z}{\partial y} = \frac{\partial z}{\partial u}\frac{\partial u}{\partial v}\frac{\partial v}{\partial y} + \frac{\partial z}{\partial v}\frac{\partial v}{\partial y} + \frac{\partial z}{\partial y}<br /> <br /> However, I have a book in front of me that says it should be<br /> <br /> \frac{\partial z}{\partial y} = \frac{\partial z}{\partial v}\frac{\partial v}{\partial u}\frac{\partial u}{\partial y} + \frac{\partial z}{\partial u}\frac{\partial u}{\partial y} + \frac{\partial z}{\partial y}<br /> <br /> I think I&#039;m correct and that they must have confused u and v. If someone could verify this for me it would be much appreciated.
 
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I agree. It think they mixed up u and v.
 
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