Overall Difficulty Verdict
The 2025 series presented a moderate-to-high difficulty level, primarily driven by the transition of Paper 12 to a Non-Calculator format. This change significantly tested students' raw numeric fluency, particularly in finding the stationary points in Question 9 through multiple integration steps with fractional exponents. Paper 22 balanced this with calculator-permitted operations but introduced heavy coordinate geometry and exponential area calculations.
Where the Marks Were Found
The marks were overwhelmingly concentrated in Calculus (39 marks), Series (19 marks), and Trigonometry (14 marks). Mastering integration (including trigonometric, quotient, and exponential forms) and standard binomial/AP/GP expansions yielded almost half of the total marks available across the two papers.
Examiner Pitfalls and Traps
- Modulus Equations: In Paper 1 Q6, many candidates forgot to split the modulus equation into both positive and negative cases (\( 2x^2 + x - 10 = -5 \)), losing up to half of the available 5 marks.
- Logarithmic Change of Base: In Paper 1 Q5(b), failing to convert \( \log_{(x+1)} 5 \) to a base-5 logarithm using the reciprocal rule led to algebraic dead ends.
- Linear Law Boundaries: In Paper 2 Q4(b), candidates frequently missed stating the range of validity for \( x \) (namely, \( 15.5 - 2x^3 > 0 \)) when converting exponential relationships to linear form.
Preparation Strategy & Future Prediction
Future candidates must practice arithmetic manipulation involving factorials and fractional indices without relying on calculators. Calculus is predicted to remain the dominant topic, with a high likelihood of relative velocity and collinear vector proofs appearing in subsequent sessions, as these were lighter in the current papers.