The <Fn forcing> order is
$$
\operatorname{Fn}(I,J)=\{p:p\text{ is a finite partial function }I\rightharpoonup J\}.
$$
It is ordered by reverse inclusion:
$$
q\le p\iff q\supseteq p,
$$
so a stronger condition specifies more values. Its maximal, or weakest, element is the empty function $\varnothing$.

Solution

Past exam of the mathematics course of the University of Cambridge / 2024 / iii / Paper 128 / 2 / a / i / Solution

 Solution

ID: past-exam-of-the-mathematics-course-of-the-university-of-cambridge/2024/iii/paper-128/2/a/i/solution