How questions are checked
Before a question appears, the site checks its answer by another calculation. For example, it substitutes a solution back into the equations, multiplies an inverse matrix by the original matrix, or checks a recurrence using a second formula.
The software tests also check that saved questions can be recreated, that invalid inputs are rejected, and that wrong answers aren’t accepted. This includes zero denominators and singular matrices. The practice tests have not been calibrated against real exams.
What automatic marking establishes
The checker can compare exact numbers, polynomials, ordered lists and finite sets in the formats shown beside the answer field. If it cannot read an answer, it asks you to check the format. It doesn’t count an unreadable answer as wrong. Intermediate checks compare the value at that step; you still need to check your working.
A correct answer alone cannot earn every method mark. Use the worked solution and marking guidance to check your reasoning, including proofs. Test results show the marks checked automatically and the marks that need someone to read your working.
Report a problem
Practice pages save the family, version and seed with your description. Local reports can be exported below. If the optional server collector is configured, a report receipt confirms delivery.
When a question fails a check
A question that fails a mathematical check is not shown. If a defect is found, the affected question type can be disabled while it is investigated. The question reference lets us recreate a reported problem.