Abstract:
This study aimed at diagnosing errors that occurred in Complex Numbers topic Among Students of preparatory year at the King Saud University. For the purpose of this study, one test was developed and administered to 214 male students who had completed pre-Calculus140 in the preparatory year ,.The results of this study revealed some common errors such as misconceptions in using the operations on complex numbers, using properties of operations on simplifications powers and numerical expressions. Some other calculation errors and careless errors were also recorded.The common errors ranged between 5.3% for conceptual misconceptions )identify real part and imaginary part( and solving linear equations involves complex numbers, and 31% for errors using the relation ) EMBED Equation.DSMT4 ( and EMBED Equation. DSMT4 to express about the square root of )-1( . The study recommended that faculty members emphasize the subject of complex numbers for freshmen and to administer diagonostic tests in order to categorize them and develop the appropriate treatment plans.
