Find and justify the inflection point.
Official paper · jm02-2022 · 2(a)(iv) · PDF 4
Official original and suggested answers ↗ · Suggested answer PDF page 9
Skills and prerequisite lessons
Working and explanation
BUILD THE REASONING
Hint 1
Set 6x−6=0.
Hint 2
Verify a change in sign, then calculate f.
Worked solution
The second derivative changes from negative to positive at x=1.
The given zero supplies its ordinate.
Inflection point (1,0).
Checks and common pitfalls: The concavity check distinguishes an inflection from a mere zero of f″.
Reasoning checklist · self / teacher assessment
- Teaching assessment checklist, independently authored. Use the original paper for official marks.
- The second derivative changes from negative to positive at x=1.
- The given zero supplies its ordinate.
Think first. Reveal a hint when the class is ready.