Official papers

Official 2023 Paper 2 · Q20

Paper 2Logic & proofCalculusAlgebra

Let ff be a polynomial with real coefficients.

The integral Ip,qI_{p,q} where p<qp<q is defined by

Ip,q=∫pq((f(x))2−(f(∣x∣))2)dx.I_{p,q}=\int_p^q\bigl((f(x))^2-(f(|x|))^2\bigr)\dd x.

Which of the following statements must be true?

  • 1. Ip,q=0I_{p,q}=0 only if 0<p0<p.
  • 2. f′(x)<0f'(x)<0 for all xx only if Ip,q<0I_{p,q}<0 for all p<q<0p<q<0.
  • 3. Ip,q>0I_{p,q}>0 only if p<0p<0.
Anone of them
B1 only
C2 only
D3 only
E1 and 2 only
F1 and 3 only
G2 and 3 only
H1, 2 and 3

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