# Problem Set: what 13-year old kids do in China

In this note, I will provide a set of problems, all copied from my homework or test assignments. I am now 13 but I suppose there are some interesting problems in my homework anyways. Why not take a look?

Assumptions(all assumptions are made from the knowledge level of Secondary 1, which is Grade 7, in China)(Just to brag, I know integration now :) ) :

• Imaginary and complex numbers do not exist.
• There is no angle greater than $180^\circ$ or less than $0^\circ$. No angle equals $180^\circ$ or $0^\circ$.
• This must be explained further: • Here $OC$ bisects $\angle AOB$ while $OD$ is not considered as a bisector at all.
• Angle bisectors are rays. Rays, straight lines and line segments are to be STRICTLY DISTINGUISHED FROM ONE ANOTHER.

Part 1
Part 2
Part 3
Part 4
Part 5
$\color{#D61F06}\small \text{Note created on 2021.3.11, three days to}~ \pi ~\text{day}$ Note by Jeff Giff
4 months, 3 weeks ago

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I think by rods you mean rays, maybe they teach a different terminology in China

- 4 months, 3 weeks ago

yup

- 4 months, 3 weeks ago

i edited that just now :)

- 4 months, 3 weeks ago