# Thread: help with easy derivative question half done

1. ## help with easy derivative question half done

how do i do the last bit?

im unsure with the "2" root x

do i put 1 over 2 root x out in front of 2 and minus 1 from 2 root x at the end.

i dont know how to write this or if its correct

2. First, note $\displaystyle \displaystyle -3 \cdot -8 =+24$

3. oh yeah sorry missed the 2 negatives

4. What's the derivative of $\displaystyle \displaystyle 2x^{\frac{1}{2}}$?

5. 2.5 over root x?

6. Half of 2 is not 2 and a half...

7. The two alternatives you gave appear to be equivalent.
$\displaystyle \displaystyle \frac{1}{x^{\frac{1}{2}}} = \frac{1}{\sqrt{x}}$

Both are correct.

8. is this the correct answer

thanks for all help

9. its right

10. Except that you wrote two different things for y'. The first, $\displaystyle y'= 24x^{-9}+ 2x^{1/2}$, is wrong because you haven't yet differentiated the second term.