Basically, CORE Math is the basic course of IGCSE Math. EXTENDED Math is in depth and it gets a little bit more complex, and teaches some new aspects of the course, that CORE Math does not teach.

When you take the EXTENDED Math, you ALSO learn the CORE Math syllabus. The extended Math exam tests you on EVERYTHING in the CORE and EXTENDED syllabus.

The main difference is that if you choose to take CORE Math, the maximum grade you can get in the IGCSE exams for that subject is a C, because the exam is easier and is less tricky. However, when you take the EXTENDED math, you maximum grade is A*.

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