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Easy Math Editor

`*italics*`

or`_italics_`

italics`**bold**`

or`__bold__`

boldNote: you must add a full line of space before and after lists for them to show up correctlyparagraph 1

paragraph 2

`[example link](https://brilliant.org)`

`> This is a quote`

Remember to wrap math in \( ... \) or \[ ... \] to ensure proper formatting.`2 \times 3`

`2^{34}`

`a_{i-1}`

`\frac{2}{3}`

`\sqrt{2}`

`\sum_{i=1}^3`

`\sin \theta`

`\boxed{123}`

## Comments

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TopNewestIt will help others if you provide some context to this. I believe that you are referring to the problem, in which we used the "CAST rule" in trigonometry. It is a simple mnemonic that helps students remember which of the trigonometric functions are positive in which quadrant. If you mark it out, you get

\[ \begin{array} { c | c} \sin & \mbox{All} \\ \hline \tan & \cos \\ \end{array} \]

Cosine is positive in the fourth quadrant,

All of them are positive in the first quadrant,

Sine is positive in the second quadrant,

Tangent is positive in the third quadrant.

This forms CAST.

There are other ways of using a mnemonic. Personally, I prefer to remember it as "A-S-T-C". You can form your own sentence with those letters in order, like "All Students Teach Calculus".

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even i remember it by a-s-t-c ;" All school to college!"

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Cat rule ahh Cool

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I mean cast

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CAST rule

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