Difference between revisions of "2024 AMC 8 Problems/Problem 22"
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− | Factoring <math>x^5+2x^4+3x^3+3x^2+2x+1</math> yields <math>(x+1)(x^2+1)(x^2+x+1)</math>. Denote <math>a, b, c, d, e</math> to be solutions of this polynomial. We can easily find one of the solutions is <math>a=-1</math>. Using the quadratic formula on the rest of the factors yields <math>b=-i, c=i, d=\frac{-1-\sqrt | + | Factoring <math>x^5+2x^4+3x^3+3x^2+2x+1</math> yields <math>(x+1)(x^2+1)(x^2+x+1)</math>. Denote <math>a, b, c, d, e</math> to be solutions of this polynomial. We can easily find one of the solutions is <math>a=-1</math>. Using the quadratic formula on the rest of the factors yields <math>b=-i, c=i, d=\frac{-1-i\sqrt{3}}{2},</math> and finally <math>e=\frac{-1+i\sqrt{3}}{2}</math>. The sum <math>a^3+b^3+c^3+d^3+e^3</math> is 3, so 3 to the third power is \boxed{27}. |
Revision as of 14:52, 21 January 2024
Problem 22
What is the sum of the cubes of the solutions cubed of ?
Solution
Factoring yields
. Denote
to be solutions of this polynomial. We can easily find one of the solutions is
. Using the quadratic formula on the rest of the factors yields
and finally
. The sum
is 3, so 3 to the third power is \boxed{27}.