A-Level MathematicsYear 2021Q10
12355 10 (i) Find the four values of x for which the curve y = √2 e–x cos x has stationary points in the range 0 < x < 4π Write your values in ascending order. [8] [Turn over 12355 12355 (ii) Show that the corresponding y values of the stationary points found in (i) form the first four terms of a geometric progression. [4] [Turn over 12355 (iii) For the geometric progression defined in (ii), find an exact value for the sum to infinity. [2]
Paper Source:GCE-Mathematics -502-Summer2021-A2 1%2C Pure Mathematics-Paper.pdf
Get full Socratic AI guidance on this question — free in the Applaa desktop app
Appy Buddy guides you step-by-step toward the answer without giving it away. Type your attempt and get instant, mark-scheme-aware clues that teach you to think like an examiner.
Applaa Desktop App
Join Applaa Community
Create your own games, learn AI concepts, program interactive apps, and share with a kid-safe community approved by parents. Free forever on Windows and Mac.
Download Free
Available for Windows and macOS · COPPA Compliant
Exam Specification Info
This question is part of the UK A-Level Mathematics syllabus. In the actual exam, structured questions typically require linking specific keywords to gain full marks. Applaa helps you drill these topics.
Syllabus levelAdvanced Level (A-Level)
SubjectMathematics
Official MarksVariable (2–6 marks)