At times we the math instructors in a classroom are not careful enough to use proper Mathematical wording, e.g. sin2 + cos2 = 1 without any reference to the angle. Improper Mathematical wording can be confusing to a student at any level, especially at high school and/or at a college freshman or sophomore level. It may hinder the students’ progress in the present and the subsequent math courses.
Goel, Sudhir and Denise Reid
"The Importance of Mathematical Wording by Math Instructors,"
Georgia Journal of Science, Vol. 70, No. 2, Article 4.
Available at: http://digitalcommons.gaacademy.org/gjs/vol70/iss2/4