Difference between revisions of "Power's of 2 in pascal's triangle"
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It is useful is many word problems (That means, yes, you can use it in real life) and it is just a cool thing to know. | It is useful is many word problems (That means, yes, you can use it in real life) and it is just a cool thing to know. | ||
More at https://artofproblemsolving.com/videos/mathcounts/mc2010/419. | More at https://artofproblemsolving.com/videos/mathcounts/mc2010/419. | ||
+ | |||
+ | == Proof == | ||
+ | |||
+ | === Long proof === | ||
+ | |||
+ | === Short proof === | ||
+ | |||
+ | === Which proof do you like better === |
Revision as of 14:18, 16 June 2019
Contents
Review
Pascal's Triangle
Pascal's Triangle is a triangular array of numbers where each number is the sum of the two numbers above it. It Looks something like this:
1 1 1 1 2 1 1 3 3 1 1 4 6 4 1
And on and on...
Patterns and properties
Conbanations
Pascal's Triangle can also be written like this
And on and on... Remember that where .
Sum of rows
1 =1 1+1 =2 1+2+1 =4 1+3+3+1 =8 1+4+6+4+1 =16
These are powers of two. Let's prove it true. (Note: There are dozens of more patterns but it would have nothing to do with powers of two).
Powers of two
Theorem
Theorem
It states that .
Why do we need it?
It is useful is many word problems (That means, yes, you can use it in real life) and it is just a cool thing to know. More at https://artofproblemsolving.com/videos/mathcounts/mc2010/419.