You might have seen this before, it seems to have made its way around the internet. It’s called **Charlie Smith’s Happy Face Math:**** **

**Cheat Sheet:**

**First Column:**

- 1st one is the
**inverse**(ie, upside down) - 2nd one is being
**squared**(hence the square) - 3rd one is being
**cubed**(hence the cube) - 4th one is
**supremum**, but you read it as “**soup**“, hence the soup 😀 - 5th one is the
**partial**differential operator, hence the “part of a face” - 6th one is
**sine**function, read as “sine”, which rhymes with “**sign**“, hence the sign

**Second Column:**

- 1st one is the “real part” of a number/function, hence, there is no imaginary part. For example,
**Re( a + bi ) = a**. Thus, you remove the i’s. - 2nd one is imaginary part.
**Im( a + bi ) = b**. In this case, you only keep the i’s. - 3rd one is the
**curl**, hence the**curly**hair. 😀 - 4th one is the
**gradient**function, read as “**grad**“, hence the smiley face looking like he just graduated from school. 😀 - 5th one is the
**log**function, hence the smiley face on a “**log**” (tree thingy)

❓ 😛 🙁 👿 ❗ 🙂 😳 😀 😮 😯 😕 😎 😆 😡 😈 😉 💡 ➡ 😐 😥

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