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**Derivatives of logarithmic functions - please help**

## Homework Statement

I am having trouble differentiating logarithmic functions. I am following this basic rule they gave us, namely: if y = ln g(x) then y' = g'(x)/g(x), but it is not working :(. Where am I going wrong?

## Homework Equations

1) ln((4 - x)/(3x + 8))

2)ln(8x^3 - 3x)^1/2

## The Attempt at a Solution

1)

**(1)(3x + 8) - (3)(4 - x)**

3x + 8 - 12 + 3x

...

(6x - 4/(3x + 8)^2)/(4 - x)(3x +8)

3x + 8 - 12 + 3x

...

(6x - 4/(3x + 8)^2)/(4 - x)(3x +8)

2)

(1/2(8x^3 - 3x)^-1/2)/((8x^2 - 3x)^1/2)

(1/2(8x^3 - 3x)^-1/2)/((8x^2 - 3x)^1/2)

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