Precalculus: Graphs and Models, A Right Triangle Approach (6th Edition) – PDF

About The Author

David J. Ellenbogen

Dr. David Ellenbogen, a mathematics professor with almost 30 years of experience teaching at the college level, has primarily worked within the community college systems of Massachusetts and Vermont. He has contributed to curriculum and developmental math committees during this time. Additionally, he has taught at St. Michael's College and The University of Vermont.

Professor Ellenbogen has been an active member of the American Mathematical Association of Two-Year Colleges (AMATYC) since 1985, serving on its Developmental Mathematics Committee and as a delegate. He has also been a Mathematical Association of America (MAA) member since 1979. He is the author of numerous textbooks covering topics from prealgebra to calculus and has delivered lectures on the use of language in mathematics.

David Ellenbogen earned his bachelor's degree in mathematics from Bates College and his master's degree in community college mathematics education from The University of Massachusetts–Amherst. He enjoys playing hiking, skiing, piano, biking, and volunteering in his free time. Currently, he serves on the boards of the Vermont Sierra Club and the Vermont Bicycle Pedestrian Coalition.

Judith A. Beecher

Professor Judy A. Beecher has an undergraduate degree in mathematics from Indiana University and a graduate degree from Purdue University. She has taught at high school and college levels with many years of developmental mathematics and precalculus teaching experience at Indiana University - Purdue University Indianapolis (IUPUI). In addition to her career in textbook publishing, she enjoys traveling, spending time with her grandchildren, and promoting charity projects for a children's camp.

Judith A. Penna

Marvin L. Bittinger

Dr. Marvin Bittinger is an esteemed mathematics professor who has taught at the university level for over 38 years. He holds the title of Professor Emeritus of Mathematics Education at Indiana University-Purdue University. Throughout his career, Professor Bittinger has authored numerous textbooks covering basic mathematics to applied calculus.

He obtained his Bachelor's degree in Mathematics from Manchester College and his Ph.D. in Mathematics Education from Purdue University. Professor Bittinger has been awarded several accolades, including the title of Distinguished Visiting Professor at the United States Air Force Academy.

Professor Bittinger has also been invited to speak at numerous mathematics conventions, most recently delivering a lecture titled "Baseball and Mathematics." He also has an interest in philosophy and theology, particularly in apologetics.