Way back in 2009
Algebra
Level
5
When is expanded, what is the sum of the coefficients of the terms with odd exponents of ?
The answer is -1.
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1 solution
Call the polynomial f ( x ) . Then the sum of the odd coefficients is 2 f ( 1 ) − f ( − 1 ) . Since f ( 1 ) = 0 and f ( − 1 ) = 2 , the answer is - 1 .