Q16 → Wrong due to silly mistake
Skipped Q20
- Time-sink solution requires heavy observation and quick identification.
- Involves quick use of inscribed angles and arcs.
Was not able to solve; did not understand substitution of
n → n-k in the solution + solution video.
Redo!
Q24 Notes:
- Easy algebra but looked difficult at first.
- Just required extra time to complete — able to solve afterwards.
Q15, Q17, Q18, Q19, Q21, Q22, Q23 → Correct
- Q17: Online solution took a long time
- I had the fastest solution : the solution was first finding g(f(x)) = 10x-1, then subbing in the 1 to get h_1(1)=9, then continuously subbing 9 back into 10x-1 so it becomes 9, 89, 899, 8999….
- Q19: Took a long time
- Found faster solution but took time to get to it: this was a least upper bound question for the slope which hits the next lattice point. If I had the answers, it would have been easier to substitute them back into and find which one would work, but I had hidden the answers. What I did next was find a few of the closest points to 102, 50 which the slope would first intersect and the slope would be as close to 1/2 as possible. After testing a few values in the form of (n/1)/(2n+1) and (n+1)/(2n) which give values close to 1/2, 50/99 was the least of these.