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Quick, easy question about diff on ln x watch

1. A question, for example

Differentiate ln(x)/ln(5)

Do you treat ln 5 as "just a number"? Or do ln (numbers) follow the same rule as differntial of ln(x)= 1/x to give 1/5?

Cheers.
2. (Original post by josh_a_y)
A question, for example

Differentiate ln(x)/ln(5)

Do you treat ln 5 as "just a number"? Or do ln (numbers) follow the same rule as differntial of ln(x)= 1/x to give 1/5?

Cheers.
ln 5 is just a number
3. it differentiates to give 0 so its just a number
4. Use the quotient rule?
5. (Original post by Smack)
Use the quotient rule?
Yeah, pretty much.

y= lnx/ln5

dy/dx= ((ln5)/x)/(ln5)^2

= 1/x(ln 5)

If anyone is interested in the answer. I just wasnt sure how to treat the ln5.

6. Aye, just treat it as a number.
7. Ypu can separate it out into ln(x) * 1/(ln(5)). The latter is just a number, and so can be used as a coefficient.

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