The Fair Use clause of copyright law is specified in sections 107-118 of (title 17, US Code), which define the limitations of the rights of the copyright owner to allow others to copy original work. This Fair Use doctrine was added to copyright law to show that, if the intention of using the copied material is for "good-faith", such as personal reading and personal education, then there should not be a problem. However, these sections are clear that four specific factors determine fair use:
- The type of copyrighted work: textbooks are made to be read by students, so in this case a small portion of a textbook may be copied. However, consider the other 3 factors.
- The purpose: if you are using it to profit from it, then it is a crime.
- The amount used in relation to the copyrighted work as a whole: Again, how much of the textbook do you want to copy? One to five pages is considered alright.
- The effect of the use on the market:- if there is a pattern of copying that will affect the sell of the textbook, then there is infringement.
As with any crime, intent, patterns, and effects are the key factors that determine criminal behavior. Copying pages (1-5 the most) of a textbook for personal purposes and without any intention of profiting, or using it against someone, should be acceptable.
In the Report of the Register of Copyrights on the General Revision of the U.S. Copyright (1961)there is a list of quite specific consessions given to copyrighting, out of which your scenario is specifically cited:
reproduction by a teacher or student of a small part of a work to illustrate a lesson
Therefore, the answer to your question is that, depending on the purpose of your usage, you may copy the pages but be careful not to end up by accident in a situation where you could be accused of infringement.