0580/22 Oct/Nov 2025, Question 18: Surds
Cambridge IGCSE Mathematics 0580 · Paper 22 (Extended) · Non-calculator · 3 marks
اقرأ هذا الحل مشروحاً بالعربي ←
The question, in short
Rationalise the denominator of 20/(4 + √6) and simplify the result.
Summarised in our own words. Use the official paper for the exact wording and any diagrams.
Solution · 3 marks
- 120/(4 + √6) × (4 − √6)/(4 − √6)
- 2= 20(4 − √6)/(16 − 6) = 20(4 − √6)/10
- 3= 2(4 − √6) = 8 − 2√6
Answer2(4 − √6) or 8 − 2√6
Stuck on a step? Read the free lesson: Surds
Practise more surds questions
Real 0580 past-paper questions, marked on your working like the exam, with a worked solution for every part.
Practise free on LemmaraMore past-paper questions on surds
Also searched as: 0580/22/O/N/25 · 0580_w25_qp_22 · 0580 w25 22 · question 18.
Lemmara is an independent study tool, not affiliated with or endorsed by Cambridge International Education. The worked solutions are Lemmara’s own.