L.O. Use the binomial expansion

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L.O. Use the binomial expansion

• If I am selecting r objects from n, the numbers
  of ways I can do this in a combination (where
  order doesnt matter) is
• nCr n!
• r!(n-r)!

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L.O. Use the binomial expansion

• (x a)2
• (x a)3
• (x a)4

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L.O. Use the binomial expansion

• (x a)2 x2 2ax a2
• (x a)3 x3 3x2a 3xa2 a3
• (x a)4 x4 4x3a 6x2a2 4xa3 a4

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L.O. Use the binomial expansion

• (x a)2 1x2 2ax 1a2
• (x a)3 1x3 3x2a 3xa2 1a3
• (x a)4 1x4 4x3a 6x2a2 4xa3 1a4

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L.O. Use the binomial expansion

• e.g. expand (x a)4
• x4 x3a x2a2 xa3 a4
• 1x4 4x3a 6x2a2 4xa3 1a4
• 1x4 - 4x3a 6x2a2 - 4xa3 1a4
• x4 - 4x3a 6x2a2 - 4xa3 a4

• First, insert the terms with powers
  ascending/descending
• Next, add the coefficients using nCr or Pascal
• Finally, insert or between each term

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L.O. Use the binomial expansion
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L.O. Use the binomial expansion
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L.O. Use the binomial expansion