Zadanie 7, Paper 2, maj 2023, TZ2, Matematyka AA IB HL

At height y the inner and outer radii are $\tan y$ and $2+\tan y$. Thus $V=\pi\int_0^{\pi/4}[(2+\tan y)^2-\tan^2y]dy=4\pi[y-\ln(\cos y)]_0^{\pi/4}=\pi^2+2\pi\ln2\approx14.2$ cubic units.

M1:express the radial boundaries in terms of y. A1:both radii correct. M1:use outer-disk minus inner-disk areas. A1:correct definite integral. A1:correct exact volume or 14.2.