Question

If f(x) = $\frac{x - 4}{2\sqrt{x}}$ then f ′(0) is

• A. 0
• B. 1
• C. Does not exist
• D. None of these

Answer 1

Answer: (C)

Does not exist

Answer 2

f(x) = $\frac { 1 } { 2 }$ $\left( \sqrt{x} - \frac{4}{\sqrt{x}} \right)$

f ′(x) = $\frac { 1 } { 2 }$ $\left( \frac{1}{2\sqrt{x}} + \frac{2}{x^{3/2}} \right)$

f ′(0) does not exist