Author note — to cover (Higher)

Higher only. Collecting like surds after simplifying every term, e.g. root 12 + root 27 = 5 root 3; unlike surds cannot combine, and root a + root b is not root(a+b). Assumes simplifying-surds; bracketed expressions live on expanding-surds. (N8)

• Fluency — direct questions on adding and subtracting surds, limited to this lesson's stated scope (4 questions).
• Application — use the same skill in unfamiliar or contextual questions without introducing a later method (4 questions).
• Check — questions built around the exclusions and likely misconceptions named in the lesson brief (4 questions).