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COnfused: what is the derivative of ln(2x)?by Arshad_Physic
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#1
Oct1709, 04:38 AM

P: 51

1. The problem statement, all variables and given/known data
What is the derivative of ln(2x)? I was just thinking about this, and I got 2 answers. I am in Calc 2 right now. 2. Relevant equations Derivative of ln(x) = 1/x 3. The attempt at a solution Since d/dx lna = (1/a)*(derivative of a) Thus d/dx ln2x = (1/2x)*(2) BUT I can also do this, I think: d/dx ln2x = 2d/dx lnx = 2*1/x = 2/x I am CONFUSED!! lol !:) Please tell me which is the correct method! :) Thanks! :) 


#2
Oct1709, 04:51 AM

P: 225

both the methods are incorrect
d/dx(log 2x)=(1/2x)d/dx(2x) =1/x 


#3
Oct1709, 06:35 AM

P: 898




#4
Oct1709, 01:11 PM

P: 51

COnfused: what is the derivative of ln(2x)?
Thanks Slider and Monty!! :)



#5
Oct1809, 10:23 AM

P: 22

(d(ln 2x)/ dx) / (d(2x)/ dx) = 2/2x/2 = 1/2x



#6
Oct1809, 04:05 PM

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#7
Oct1809, 09:58 PM

P: 22

ohh sorry I calculatd, derivative of ln2x wrt to 2x.



#8
Oct1909, 09:06 AM

P: 24

1/2x



#9
Oct1909, 09:21 AM

HW Helper
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#10
Jan1810, 05:42 AM

P: 2

anti derivative of 1/x or x^1 = ln (x) natural log of x =ln x +c so the derivative of c + ln (2x)dx=1/2x +C'



#11
Jan1810, 12:42 PM

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