Common Mistakes in IB Mathematics AA
Success in the IB Mathematics AA exams often comes from avoiding common errors that can cost valuable marks. Awareness of these pitfalls is the first step to correcting them in your own work.
Execution and Notation Errors
- Calculator in Degree Mode Always check your calculator is in radians mode, as it is the default for all calculus and trigonometry questions.
- Incorrect Rounding Give final answers to three significant figures unless the question specifies otherwise. Use full calculator accuracy for intermediate steps.
- Ignoring 'Show That' Instructions For 'show that' questions, you must provide a clear, step-by-step argument. The final answer is given, so marks are for the logical process.
- Confusing 'Exact' and 'Approximate' If a question asks for an exact value, leave your answer in terms of pi, roots, or fractions (e.g., √2/2, not 0.707).
- Missing Units in Kinematics Remember to include the correct units (e.g., m/s for velocity, m/s² for acceleration) in your final answers for kinematics problems.
Conceptual Misunderstandings
- Forgetting Conditions for Formulas Remember the conditions for using a formula, like the sum of an infinite geometric series requiring |r| < 1.
- Misinterpreting Command Terms Understand the difference between 'write down' (no working needed), 'calculate' (working needed), and 'explain' (requires a written sentence).
- Assuming a Diagram is to Scale Never assume angles or lengths from a diagram. Rely only on the information given in the text of the problem.
- Mixing up Product and Chain Rules Clearly identify the structure of a function before differentiating. Write down u and v for product/quotient rule to avoid confusion.