About the Authors

Thushan Hettige

Dr Thushan Hettige is the Managing Director and the most senior content developer at Decode, also authoring the Decode HSC Chemistry title. His talent in Mathematics has been apparent from his youth, when he became the first primary school student in Australia to complete the Kumon Mathematics programme in 2005. His achievements in Mathematics during his secondary schooling is no less impressive, and include a 2011 VCE (Victorian Certificate in Education) ATAR score of 99.95 with top scores in his Mathematics subjects, and a Silver Medal in the 2011 Australian Mathematical Olympiad.
Thushan has since racked up extensive tutoring experience spanning nearly a decade, and he has utilised his unique and original teaching methods in his detailed solutions to the Mathematics Advanced problems.

Jeffrey Yang

Jeffrey Yang graduated from Sydney Boys High School in 2017 with an ATAR of 98.85, practically acing Mathematics Extension 1 and Mathematics Extension 2 with HSC marks of 99 in both subjects. He has since tutored HSC Mathematics Extension 1 and Extension 2 at the highly reputed Ninety Plus Education Centre, as well as HSC Mathematics Advanced. Jeffrey is currently completing his Bachelor of Science and Computer Science at the University of New South Wales, majoring in Pure Mathematics and Artificial Intelligence. Jeffrey's talent at decoding (pardon the pun) the difficult concepts in Mathematics Extension 1 is very clear from his extremely high quality detailed solutions to the Mathematics Extension 1 problems.

Tim Koussas

Tim Koussas is Decode's resident Mathematics expert, with his credentials in Mathematics being phenomenal. After graduating with top scores in his Mathematics subjects in the 2012 VCE (Victorian Certificate in Education), Tim has proceeded to obtain an average of close to 100 in his Mathematics subjects at undergraduate level, before embarking on his PhD at La Trobe University (Melbourne) in Pure Mathematics. Tim has been involved in the development of all of Decode's Mathematics titles, both in the HSC and the VCE.