You would typically measure a math book using units of length, width, and height.

Here are some common units:

* Inches (in): A common unit in the US.

* Centimeters (cm): A common unit in the metric system.

* Millimeters (mm): A smaller unit in the metric system.

You could also measure the weight of the book using units like:

* Pounds (lb): A common unit in the US.

* Kilograms (kg): A common unit in the metric system.

The specific unit used depends on the context and the desired level of precision.