metalman213
Sixth Man
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That explanation of the chain rule never made much sense to me because it implies that the derivative of f(x) = (ax+b)^c is equal to f'(x) = derivative of (ax + b) times the derivative of c... i like the u substitution explanation more where, in the case of (ax + b)^c, you rewrite it as u = ax + b and thus u^c then its dy/dx = dy/du x du/dx and you use the power rule c*u^c-1 (derivative of y with respect to u... in other words dy/du) multiplied by the derivative of u which is the derivative of (ax +b) (derivative of u with respect to x... in other words du/dx...This is using the chain rule, which states d/dx of (ax+b)^c is the derivative of the outside term multiplied by the derivative of the inside term.
It's a pain to get used to at first, but it will become on of the most common derivative rules you'll apply in calculus.
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