first.. its about the quotient rule(adsbygoogle = window.adsbygoogle || []).push({});

say we are findnig the derivative of something such as x / (x-1)^2

for the derivative of the denominator, do we treat the denominator's exponent as 2 or -2, since its a denominator? (confused with the perspective and approach you take)

today i was exposted to some very confusing stuff

TAKE DERIVATIVE

1. y = ln5x

y' = 1/5x (5x) = 1/x

chain rule was applied

but how come u take out 5x?!?!?!. u only take out values that make the derivative an "impure" x or whatever, shouldnt u just take out the 5?!!?!

whats being added on to 1/x is 5 isnt it? , not 5x

if a 5x was added on, that would be 1 / 5x^2

this doesnt make sense

also, today we took higher ordre derivatives

y=sin2x

y' = 2cos2x i know deriv of sin is cos, but why is there a new coefficent of 2 in front???

y'' = 2(-sin2x)(2) = -4sin2x <--- what the heck? okay so that kind of make sense, but i dont see chain rule applied to y'

y''' = -4cos2x if the transition of cos to sin is multiplied by -2, then why does the coefficient say the same when sin -> cos???? arghhhh

note that these are all correct for sure.. just that i dont understand them

even more confusing is the d/dx thing

sometimes its like dy/dx , d/dx, whatever, i dont get it at all,, i know its derivative something respect to x, but i just dont understand how it works

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# Homework Help: Questions about derivatives and etc

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