1. ## Functions

For each function f(x) find f'(x)

A) f(x) = log(1/2) x

the 1/2 is subscript.

I got the answer ln(x) / -ln(2).
Is this correct i don't feel confident in it.

2. Hello,
Originally Posted by theflyingcow
For each function f(x) find f'(x)

A) f(x) = log(1/2) x

the 1/2 is subscript.

I got the answer ln(x) / -ln(2).
Is this correct i don't feel confident in it.
Not really !
What you got is another expression for f :

$\log_{1/2}(x)=\frac{\ln(x)}{\ln(1/2)}=-\frac{\ln(x)}{\ln(2)}$

Treat $\ln(2)$ as a constant and then find the derivative !

MOOOOOOOOOOO

3. How do I treat it as a constant. What I have is how far I am with keeping up with the teacher

4. Originally Posted by theflyingcow
How do I treat it as a constant. What I have is how far I am with keeping up with the teacher
If a is a constant, then the derivative of $a \cdot f(x)$ is $a \cdot f'(x)$

So $\left(-\frac{\ln(x)}{\ln(2)}\right)'=-\frac{1}{\ln(2)} \left(\ln(x)\right)'$

what's the derivative of the logarithm ?

5. x / ln10 i believe

6. wrong mate the derivate of ln (x) is:

$\frac{{d}}{{dx}}ln (x)=\frac{{1}}{{x}}$

7. so where do i go (-1/ln(2)) * (1/x)