1964 AHSME Problems/Problem 20
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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. Unknown error_msg)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 | |
| 1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 • 26 • 27 • 28 • 29 • 30 • 31 • 32 • 33 • 34 • 35 • 36 • 37 • 38 • 39 • 40 | ||
| All AHSME Problems and Solutions | ||
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