Exam-style question
Try this first
Which first step is most appropriate when simplifying a surd such as sqrt(72)?.
- A.B2: choose the method that matches Use and manipulate surds
- B.Use any familiar GCSE calculation even if it ignores Use and manipulate surds
- C.Write only the final answer without showing the mathematical method
- D.Change the notation or restrictions to make the algebra look simpler
Model answer
What a good answer should say
- The correct answer is B2: choose the method that matches use and manipulate surds.
- It is correct because simplification begins by identifying the largest square factor, then rewriting the surd in exact simplified form.
This answer is tied to the objective: B2 Use and manipulate surds, including rationalising the denominator..
Explanation
Why this works
Use the explanation to connect the worked answer back to B2 Use and manipulate surds, including rationalising the denominator..
The correct option, B2: choose the method that matches Use and manipulate surds, is best because simplifying a surd begins by identifying square factors and keeping the value exact. This B2 item checks that the method preserves the surd form rather than using a rounded decimal, unsupported cancellation, or unnecessary rationalising.
Maths method check
- Topic focus: Pure Mathematics.
- Question style: practice.
- Reasoning demand: recall.
- Check the operation, notation, units, and final answer form against the question before moving on.
Common mistake
No common mistake is linked to this question yet.