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Differentiating lnx

I understand that integrating 1/x is lnx and 1/2x is 1/2ln2x.

I also know that differentiating lnx is 1/x and ln3x+1 is also 1/x but as differentiating and integrating are reverse functions, why is the differential of ln2x+1 not 1/2x+1, as surly if you integrate 1/x you won't get ln2x+1. Is it covered by the +c?
You're right, it's covered by the +c. So yeah if you differentiated ln3x into 1/x then you integrated back it would be lnx +c and c=ln3 in this case. In fact I was thinking the exact same thing yesterday I think :P.
Reply 2
Original post by black1blade
You're right, it's covered by the +c. So yeah if you differentiated ln3x into 1/x then you integrated back it would be lnx +c and c=ln3 in this case. In fact I was thinking the exact same thing yesterday I think :P.


Ah I see, cheers!

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