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

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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 $180^\circ$ $18 0^{\circ}$ or less than $0^\circ$ $0^{\circ}$ . No angle equals $180^\circ$ $18 0^{\circ}$ or $0^\circ$ $0^{\circ}$ .
- 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
$\color{#D61F06}\small \text{Note created on 2021.3.11, three days to}~ \pi ~\text{day}$

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Comments

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

Jason Gomez - 3 months ago

yup

Jeff Giff - 3 months ago

i edited that just now :)

Jeff Giff - 3 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$