Hey... i was hopeing somebody can help me with a homework question... its about vector calc.... taking the deriviative.(adsbygoogle = window.adsbygoogle || []).push({});

d/dx[r(t) dot r(t)] = r'(t) dot r(t) + r(t) dot r'(t) = 2r'(t) dot r(t)

I know it sounds sillly, but i was just wondering how on earth they got

2r'(t) dot r(t) ????

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# Homework Help: Vector Calculus

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