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# Math Help

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Anyone good at calculus? I need help!

what is the derivative of this natural log.

ln (square root sign) (2x+3)/(4x+5)

then I have to find f'(0)

If you can find the derivative I can find f'(0) easy

Edited to add: I can do the quotient rule but the square root is throwing me off.

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I'm a bit rusty, but isn't the derivative of a natural log x just 1/x? Where are you having trouble?

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Yea thats correct....for x but not for the problem I'm working on. There a lot more work to it.

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I'm rusty too but I'm pretty sure it is 1/x.

Orfun #4
Juego Hombre Rodriguez

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to find the derivative of a natural log you put take the derviative of the function over the function so the derviative of x = 1 so yes f(x) ln x = 1/x But the problem I am doing has more too it.

The SQ root over those whole function si messing me up somehwere and I can figure it out

Any math majors out there?

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Quote

The SQ root over those whole function si messing me up somehwere and I can figure it out

below

i left the ln out, if fixed it.

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you're so smart its sexy

Jen
Arianna Frances

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Would you mind working that again. I left out ) after 3 and ( before the 4.

ln (square root sign) (2x+3)/(4x+5) is correct now here and above.

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f(x) = ln ( sqrt( (2x+3)/(4x+5) ) )

And you need to find f'(0).

First you can simplify a lot before actually finding the derivative.

f(x) = 1/2 ln (2x+3) - 1/2 ln(4x+5)

Also the derivative of ln(x) is 1/x dx not just 1/x.

so f'(x) = 1/(2x+3) - 2/(4x+5)

f'(0) = 1/3 - 2/5;

-Nick
--
I used to pray to God for a bicycle.
Then I realized God doesn't work that way.
So I stole one and prayed for forgiveness.

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Thats it! Awesome. Thanks you. -1/15 is one of the answers!

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f(x) = 1/2 ln (2x+3) - 1/2 ln(4x+5)

Yea, looking back at my work I did get too here, but using another example in the book somewhere I went screwy.

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Only math figures I'm good with are 36-24-36

Nice!

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