What is the limit of the following? lim(h->0) ((2+h)^0.5 -(2)^0.5)/h
Note: I'm struggling to make the denominator positive.
What is the limit of the following? lim(h->0) ((2+h)^0.5 -(2)^0.5)/h
Note: I'm struggling to make the denominator positive.
First way:
$$\lim_{h\to 0}\frac{\sqrt{2+h}-\sqrt2}h=(\sqrt x)'|_{x=2}=\frac1{2\sqrt2}$$
Second way:
$$\lim_{h\to 0}\frac{\sqrt{2+h}-\sqrt2}h=\frac{2+h-2}{h(\sqrt{2+h}+\sqrt2)}=\frac1{\sqrt{2+h}+\sqrt2}\xrightarrow[h\to 0]{}\frac1{2\sqrt2}$$