Let be a convex quadrilateral inscribed in a circle and satisfying . Points and are chosen on sides and such that and . Prove that .

Milan Haiman

I’m preparing AIME and USA(J)MO.
Can you recommend specifically Number theory books?
I already had intro NT of AOSP.
Thank you

I have been doing contest math for around 2 to 3 years, and have taken PreAlgebra(AB), Algebra(AB), ... to Intermediate C&P. Over time, I have noticed that I have been being able to study less effectively. For example, when I start doing some challenging problems, my brain just fogs up. Even though I have understood the method for them, I hit the wall the second I read the problem. This has been a bigger and bigger issue, as there is this clear threshold for me and it is horribly frustrating. I would very much appreciate some advice, or some other methods.

Another problem, as of lately, I have been messing up on contests. I got an 21 on the AMC8, but then flopped on the current Gauss contest with an estimated 2-3 sillies, and the Pascal too, with 4 wrong. I don't know what's happening, but it's the same thing, I know how to do the problem (ex. I know its Modular Congruences, but I can't apply it) and end up wasting time. I would also appreciate some advice on this too. Thanks in advance! :)

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Hi, can anyone recommend a few books or websites/sources which could help me prepare for this year's AMC 10? I am aiming to qualify for AIME. Also, in addition to the recommendations for AMC 10, it would be great if somebody could also recommend some sources to prepare for a competition like BmMT (for BmMT, I am aiming for top 20%) or just middle/high school math contests in general.

What an emotional roller coaster the past 34 days have been.

Congrats to all that qualified!

For this theorem, Evan says that the power of point with respect to is greater than 0 if lies between and . (I've underlined it). But, I'm a little confused as I thought the power was and since is inside the circle, wouldn't the power be negative since ?

Ok, so right now, I am doing the EGMO book by Evan Chen, but when it comes to problems, there are some that just genuinely frustrate me and I don't know how to deal with them. For example, I've spent 1.5 hrs on the second to last question in chapter 2, and used all the hints, and I still am stuck. It just frustrates me incredibly. Any tips on managing this? (or.... am I js crashing out too much?)

Can students outside the US take the AIME if they earn a qualifying score?

Hey AOPS!!!!! :D :D :D :D :D

Hope you're all excited for the summer! As the summer approaches and you're all beginning to get back on the math grind I hope that you'll all also do some leisurely math reading/discovery!!

Check out this month's MathEXplained Magazine issue where we explore:
1. The math behind sports betting
2. The birthday paradox
3. Mathematicians born in May and their contributions to math
4. The ulam spiral
5. The surprising past behind the cubic formula (INSANE BEEF)

You can read this months issue on our website at https://mathexplained.github.io/ or on this google drive file

Additionally, if you are interested in sharing our own niche mathematical interests, I would encourage you to apply for a staff position at: [url][/url]https://tinyurl.com/MEXapply

Don't forget to join our discord server at https://tinyurl.com/MEXplained to let us know who's side you're on!!