(adsbygoogle = window.adsbygoogle || []).push({}); chain rule someone help plz

1. let z=y^2-x^2cosy; x=t^3 y=cost, find dz/dt

2. let z=(x-y)^3;x=u+2v,y=2u-v,find dz/dv

my attempt:

so i know the chain rule is (dz/dx)dx+(dz/dy)dy

1. should i substitute the x and y into t first or should i do the partial derivative first?

2. same thing what should i do first?

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# Homework Help: Chain rule someone help

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