Showing posts with label student reflection notes. Show all posts

Thursday, October 2, 2025

2016 AMC 12 A Reflection Notes from H

2016 AMC 12A Log

✅ Correct

Problems 1 → 23

❌ Wrong

Problems 24, 25

Problem 24: Had the right idea but didn’t continue far enough.
Problem 25: Didn’t understand the problem even after a video.

📘 Embedded Problems

Problem 24 (paraphrase)

There is a smallest positive real number a such that one can choose a positive real b making all roots of the cubic \(x^3 - a x^2 + b x - a\) real. For this minimal a, the corresponding b is unique. What is that value of b?

AoPS #24 (official) AoPS video #24 Extra discussion

Problem 25 (paraphrase)

Let k be a positive integer. Bernardo writes perfect squares starting with the smallest having k + 1 digits; after each square, Silvia erases the last k digits of it. They continue until the final two numbers left on the board differ by at least 2. Let f(k) be the smallest positive integer that never appears on the board. Find the sum of the digits of \(f(2)+f(4)+f(6)+\cdots+f(2016)\).

Note from Mrs. Lin : To understand this question more in details, try

this video, starting at 24: 11.

AoPS #25 (official) AoPS video #25

Saturday, September 13, 2025

2017 AMC 12 B Reflection Notes from H

2017 AMC 12B — Practice Log

Quick reflections and timing notes.

Q1–Q23: all correct ✅ Q22: time sink ⏳ Q24–Q25: not answered ❌

Notable Questions

#13: Took me a while; need to keep practicing Burnside's lemma/technique. (note to self: revisit topic & drill)
#22: Became a time sink. Pause sooner; sketch structure, estimate difficulty, and decide quickly whether to skip.
#24: Didn’t understand the question—unclear how to set up the average. Re-read carefully; translate wording to variables first.
#25: Ran out of time.

Process & Timing Notes

Not enough time at the end—was able to draw the diagram but didn’t complete the setup.
For average/setup questions: define variables immediately, write the equation before computing.
When a problem starts ballooning (>3–4 minutes without structure), mark and move.

Follow-Up Plan

Monday, September 1, 2025

9/1/2025 Student Reflection Note from H

2018 AMC 12A Notes 🎉

😊 Only 2 Wrong — Great Job!

Wrong

22: Not sure how to express √abi cleanly.
Couldn’t manage complex numbers or split the area into 4 pieces.
25: Was able to get the powers of 10 and simplify, but not the final casework step.

Right

15, 16, 17, 18, 19, 20, 21, 23, 24

8/31/2015 Student reflection notes from H

2019 AMC 12B Notes

Problems 20–25 → Wrong

20: Tried coordinate bash but didn’t realize AOBX is cyclic.
21: Very close, but made a mistake in casework.
22: No idea how to estimate.
24: Confusing — unsure how to approach.
25: Imaginary numbers solution was smart.
Also homothety solution was smart too.

Problems 15–19, 23 → Right

Saturday, August 23, 2025

8/23/2025 student reflection notes from H ～ Welcome back to the States.

2019 AMC 12A – Reflection Log

Quick notes on misses, themes, and time sinks.

Incorrect

#22. Problem and Solutions
#24. Found all prime exceptions but missed 4 — Problem and Solutions
#25. Got after hint → need work on angle chasing in cyclic quadrilaterals — Problem and Solutions

Correct

Problems solved:

#15 #16 #17 #18 #19 #20 #21 #23

#17 → learn Newton's Sums
#23 → algebra took a long time.

Next Steps

Drill Newton’s Sums identities; derive first 3–4 power sums using Vieta.
Re-check prime-exception logic; include 2 and 4 in prime-exception checklist.
Daily 10-min cyclic quadrilateral angle-chasing (use Ptolemy, equal angles, arc marks).
Practice pacing to avoid #17-style time sinks; enforce a 2-minute “move on” rule.
Algebra endurance reps (substitution, factoring patterns), especially for de-jangling #23-type problems.

Tuesday, August 19, 2025

8/19/2025 student reflection notes from H

2020 AMC 12B Reflections

Wrong Questions

Q19: Not sure how to approach. My casework method was too complicated.
Q21: Solution made sense. I made the substitution u = 70n + 50, but couldn’t expand it properly.
Q23: Saw that n = 2, n = 3 worked, but I couldn’t eliminate later cases of n ≥ 4.
Q25: Solution seemed easy, but I didn’t see the graphical method earlier. I have to get better at identifying that.

Correct Questions

Q15: Solved correctly.
Q16: Solved correctly.
Q17: Solved correctly.
Q18: Solved correctly.
Q20: Solved correctly.
Q22: Solved correctly.
Q24: Solved correctly.

Friday, August 15, 2025

8/15/2025 2020 AMC 12 A student reflection notes from H while in India

2020 AMC 12A Log

Wrong

Q18 – Tried other equation → could not solve
Q23 – Hard casework (I could guess if correct, more of a check)
Q24 – Weird set, specialized translations in geometric problem
Q25 – Really hard Q. Required graphing + adaptation for 2π trap but not confident/solid

Right

Q15
Q16
Q17
Q19
Q20
Q21
Q22

Thursday, August 14, 2025

8/14/2025 SAT/AMC 12 student reflection notes from Ay

1) Reviewed the attached problems and solutions 2) Reviewed the SAT vocabulary words and tried the SAT questions. I was able to answer all three questions correctly. 3) Attempted the 2023 AMC 12 A. I skipped these questions- #15, #21, #22, #24 and #25 Rest all questions were answered correctly.

Thursday, August 7, 2025

8/6/2025 2014 AMC 12 B student reflection notes from H while in India :)

2014 AMC 12B Log

Correct:

15
16
17
18 – took time
19
20
22 – time-sink
24
25

Wrong:

21 – struggled with too many variables
23 – no idea how to approach

Sunday, August 3, 2025

7/27/2025 2023 Mathcounts state sprint student reflection notes An

2023 Mathcounts State Sprint:

Q13 Rate silly mistake made miscalculation when I was trying to find the rates always double check if the rates if it make sense with the question

Q21 number theory had an idea but it didn't work because I didn't count all the ordered triplets
Learn how to do these problems fast and accurately

Q22 probability didn't know how to do it