###### Example1.7.12Square Root

The symbol $$\sqrt{b}$$ has meaning when $$b\geq0\text{.}$$ It means the positive number that can be squared to result in $$b\text{.}$$

1. $$\sqrt{9}=3$$

2. $$\sqrt{2}\approx1.414$$

3. $$\sqrt{\frac{9}{16}}=\frac{3}{4}$$

4. $$\sqrt{-1}\text{ is undefined}$$

in-context