Need Help

Hi..I am Sushmita from India. My weakest topic is Combinatorics. I get confused when to multiply and when to add the combinations. But I want to learn it badly.I want to be the best at at it. Please help!!

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Easy Math Editor

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.

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Use the emojis to react to an explanation, whether you're congratulating a job well done , or just really confused .
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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}`	$\boxed{123}$

Comments

Hi Sushimita,

It is nice to meet you! For help on combinatorics problems I frequently reference the Olympiad section of our techniques page. Scroll down to the subheading "Combinatorics" and you will find many posts on essential concepts with worked examples.

Overall though, I think the best way to learn on Brilliant is just to do your best on the problems, lose your fear/shame at being wrong, and enter the solution discussions to learn as you go from the methods of others. Learning well from solutions is a skill and takes some getting used to. In general when I read a solution to a problem I did not understand, I read through it step by step and try to justify to myself why they chose to do it the way they did. If you do this and do not understand a step, please ask. People will be happy to help you and chances are you are not the only one with the question.

Peter Taylor Staff - 7 years, 5 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}`	$\boxed{123}$