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# quick differential question (3 terms) Watch

1. y = xz

therefore dy/dx = x(dz/dx) + z

can anybody explain why this is? lol

EDIT: nvm.. i just remembered from last year that dy/dx = dy/dz x dz/dx
2. (Original post by ucasisannoying)
y = xz

therefore dy/dx = x(dz/dx) + z

can anybody explain why this is? lol

EDIT: nvm.. i just remembered from last year that dy/dx = dy/dz x dz/dx
This has nothing to do with the chain rule. This is done using the product rule.
.
3. (Original post by Farhan.Hanif93)
This has nothing to do with the chain rule. This is done using the product rule.
.
oh damn... works for both rules though, what exactly is stopping us from using the chain rule here? i thought the principle that dy/dx = dy/du x du/dx where u is a variable works regardless
4. (Original post by ucasisannoying)
oh damn... works for both rules though, what exactly is stopping us from using the chain rule here? i thought the principle that dy/dx = dy/du x du/dx where u is a variable works regardless
Chain rule won't work here, with 2 variables think you'd take partials differentials for it to work, instead this is simply reverse product rule,
5. (Original post by Kevlar)
...this is simply reverse product rule
What is this, I don't even...

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