# Weekend Wiki Party 8 - Trigonometry

This week our wiki project is to improve some of the trigonometry pages on the site. Thanks to your contributions from previous wiki weekend parties, we have collectively made hundreds of edits to wiki pages and helped Brilliant's 1,000,000+ FB followers learn, collaborate, and solve problems together!

To participate, just jump in and write something on one of the following pages, and then leave a comment to let us know that you contributed. To guide you in crafting the wikis, we have included section outlines, identities in need of proofs, and examples in need of solutions. We need your help to replace the many "???" throughout these wikis with your brilliant proofs and solutions. Or feel free to add a new section or submit your own example. Every contribution helps!

Note by Calvin Lin
6 years, 1 month ago

This discussion board is a place to discuss our Daily Challenges and the math and science related to those challenges. Explanations are more than just a solution — they should explain the steps and thinking strategies that you used to obtain the solution. Comments should further the discussion of math and science.

When posting on Brilliant:

• Use the emojis to react to an explanation, whether you're congratulating a job well done , or just really confused .
• Ask specific questions about the challenge or the steps in somebody's explanation. Well-posed questions can add a lot to the discussion, but posting "I don't understand!" doesn't help anyone.
• Try to contribute something new to the discussion, whether it is an extension, generalization or other idea related to the challenge.

MarkdownAppears as
*italics* or _italics_ italics
**bold** or __bold__ bold
- bulleted- list
• bulleted
• list
1. numbered2. list
1. numbered
2. list
Note: you must add a full line of space before and after lists for them to show up correctly
paragraph 1paragraph 2

paragraph 1

paragraph 2

[example link](https://brilliant.org)example link
> This is a quote
This is a quote
    # I indented these lines
# 4 spaces, and now they show
# up as a code block.

print "hello world"
# I indented these lines
# 4 spaces, and now they show
# up as a code block.

print "hello world"
MathAppears 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} $\boxed{123}$

Sort by:

- 6 years, 1 month ago

I have an advice. Use degrees instead of radians. The page is for newbies who might not have studied about radians. Thanks. $\ddot\smile$

- 6 years, 1 month ago

Oh okay! Good suggestion, thanks.

- 6 years, 1 month ago

Thanks! Keep it up!

- 6 years, 1 month ago

sir, can we add wiki on INVERESE TRIGONOMETRY also???

- 6 years, 1 month ago

Sure. Add a wiki on any topic you like. $\ddot\smile$

- 6 years, 1 month ago

Yeah sure.....I'll collect all the required wikis for the topic and post it tomorrow

- 6 years, 1 month ago

Staff - 6 years, 1 month ago

Sir, i've added a wiki. can u see if its fine

- 6 years, 1 month ago

There are already pages on inverse trigonometry, functions, identities and graphs(this one is empty). So you don't need to make new Wikis (unless it's a completely new subtopic you wanna write about), you can go through these and add any knowledge they lack.

- 6 years, 1 month ago

Is there a sum to product identity for $\tan x+\tan y$? The only one I can think of is $(\tan(x+y))(1-\tan x\tan y)$, or maybe something like $\frac{\sin(x+y)}{\cos x\cos y}$.

Oh, and, could someone please give me a link to the wiki from where I can start studying matrices? Can't find it. Thanks :)

- 6 years, 1 month ago

There isn't a "nice" version of it. Another way of writing it, where we only use $\tan$, is $\tan x + \tan y = \tan ( x + y) ( 1 - \tan x \tan y )$. Do you see how to get there from what you have?

We haven't started on the matrices skills as yet, because we rather focus on filling out existing areas first.

Staff - 6 years, 1 month ago

That should be $\tan(x+\color{#D61F06}{y})(1-\tan x\tan y)$

- 6 years, 1 month ago

Thanks! fixed.

Staff - 6 years, 1 month ago

Okay thanks! Yeah, I can get to the formula.

- 6 years, 1 month ago