Derivative of sqroot

Code: 
          x + 3         x + 3
f(x) = ---------- =  ----------- = x^(1/2) + 3x^(-1/2)
         sqrt(x)       x^(1/2)
 
I've fixed my post. Have another go and please show us your steps so we can be more helpful!
 
f(x) = (x-3)/(x^(1/2))
f(x) = x/(x^(1/2)) - 3/(x^(1/2))
f(x) = x^(1/2)* -3x^(1/2)... oops! -3/(x^(1/2)) = -3x^(-1/2)
f'(x) = 1/2x^(-1/2)-3/2x^(-1/2)
Click to expand...
* This comes from x^1 / x^(1/2) = x^(1- 1/2) = x^(1/2).
 
That negative should be positive because at some point we multiplied (-1/2) by -3.

And may I stress the helpfulness of using parantheses: if you meant
1/(2sqrtx) - 3/(2x^(3/2)), then after the negative you are correct.
 
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