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Help differentiation

I don’t get why I can’t do this to differentiate ln3x becaus the answer is actually 1/3x
ln(3x) = ln(3) + ln(x)
so ...
Reply 2
the answer is 1/x. ln(3x) differentiate the whole thing so do, dy/dx of ln3x. that gets you 1/3x. but then you also have to differentiate the inside of the bracket ie, the 3x. dy/dx of 3x is 3. times the two results together so, 1/3x * 3. this gets you 3/3x. which can then get simplified to 1/x. its just applying chain rule
Is my working correct then??
Original post by mqb2766
ln(3x) = ln(3) + ln(x)
so ...

Is my working correct ?
the derivative of ln(3x) is 1/x, for either of the explanations given above.
Original post by mqb2766
ln(3x) = ln(3) + ln(x)
so ...

How would you differentiate ln(3) + ln(x) to get 1/x?
Original post by toxicgamage56
How would you differentiate ln(3) + ln(x) to get 1/x?


derivative of ln(x) is 1/x and the derivaive of ln(x) + c is again 1/x. c = ln(3) in this case.
Original post by mqb2766
derivative of ln(x) is 1/x and the derivaive of ln(x) + c is again 1/x. c = ln(3) in this case.

Oh I see, I get it now. Thanks.
Original post by toxicgamage56
Oh I see, I get it now. Thanks.


Do u have ur a level exams this year?
Original post by Alevelhelp.1
Do u have ur a level exams this year?

Yes
Original post by toxicgamage56
Yes


Same how’s revision going?? R u doin aqa Alevel maths ?

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