1964 AHSME Problems/Problem 20
Problem 20
The sum of the numerical coefficients of all the terms in the expansion of is:
Solution
For any polynomial, even a polynomial with more than one variable, the sum of all the coefficients (including the constant, which is the coefficient of ) is found by setting all variables equal to . Note that we don't have to worry about whether a constant is a coefficient of an "invisible $x^0y^0" term, because there is no such term here.
Setting$ (Error compiling LaTeX. ! Missing $ inserted.)x=y=1(-1)^{18}1\boxed{\textbf{(B)}}$.
See Also
1964 AHSC (Problems • Answer Key • Resources) | ||
Preceded by Problem 19 |
Followed by Problem 21 | |
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