Drag the input value (point) on the horizontal axis left and right to see if the input shown has an output value.

1. Can you square $\frac{-1}{2}\text{?}$ ? yes no
2. Can you square $2.1\text{?}$ ? yes no
3. Use a calculator to help you answer this next question.
   Is there any number you can’t square (multiply by itself)? ? yes no