## mathhatesme123 2 years ago How to Expand (x + 2y)^5

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1. hal_stirrup

(x+2y)(x+2y)(x+2y)(x+2y)(x+2y)

2. TuringTest

^that is probably the ugliest way to do it I would use either Pascal's triangle or the binomial theorem

3. hal_stirrup

it take a long time if you do it that way. true

4. hal_stirrup

i like to show the long way so it becomes more clear. Pascal's triangle is goog way to do it. or a calculator!!

5. TuringTest

binomial theorem:$(a+b)^n=\sum_{k=0}^n\binom nka^{n-k}b^k$where$\binom nk={n!\over k!(n-k)!}$

6. TuringTest

if the binomial theorem looks like Greek to you then I would go with Pascal's triangle since it is only to the 5th power

7. mathhatesme123

thank you :)

8. TuringTest

welcome!

9. hal_stirrup

nice