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

Since both my questions are on the same topic, i'll throw them both in here

1. Find dz/dt for z=(x^2)(t^2), x^2+3xt+2t^2=1

2. Show that if u=xy, v=xy and z=f(u,v) then:

x.dz/dx-y.dz/dy=(x-y)dz/dv

2. Relevant equations

3. The attempt at a solution

1. I only know how to do this when I have something like:

z=x+y, x=t+..., y=t+...

2. I realise that after I get the partial derivatives I just have to substitute back to prove this, but i'm not sure how to get the derivatives. I think it's the z=f(u,v) that has me lost

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# Multivariable functions - chain rule

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