Hello everyone,i had a question..i have the following problem, i'm suppose to find the first partial derivatives:(adsbygoogle = window.adsbygoogle || []).push({});

f(x,y,z,t) = xyz^2*tan(yt);

I got all the partial derivaties right but the fy, they get:

fy = xyz^2*sec^2(yt);

when i do it, i get:

fy = xz^2*sec^2(yt)*t = txz^2*sec^2(yt);

Arn't u suppose to think x,z and t are all constants? if thats the case, when u use the chain rule inside the sec^2(yt), d/dt(yt) = t isn't it?

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# Homework Help: Partial derivatives, why is the fy this?

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