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simanliu
Please show proof of Chain Rule
This is the proof that I was shown when I learnt the chain rule http://math.rice.edu/~cjd/chainrule.pdf
thank you so much, i will be sure to check it out!
What is there to prove. If u is differentiable function of x and x is differentiable function of t then u is diffrentiable function of t and \[\frac{ du }{ dt } = \frac{ du }{ dt }\frac{ dx }{ dx } = \frac{ du }{ dx }\frac{ dx }{ dt }\] because \[\frac{ dx }{ dx }=1\]