Art of Problem Solving

2000 AIME II Problems/Problem 9: Difference between revisions

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== Solution ==
== Solution ==
{{solution}}
Note that if z is on the unit circle in the complex plane, then  
Note that if z is on the unit circle in the complex plane, then  
Let <math>z = a + bi</math> and we have <math>z = e^i\theta</math>  and <math>\frac 1z= e^{-i\theta}</math>
Let <math>z = a + bi</math> and we have <math>z = e^{i\theta}</math>  and <math>\frac 1z= e^{-i\theta}</math>


== See also ==
== See also ==
{{AIME box|year=2000|n=II|num-b=8|num-a=10}}
{{AIME box|year=2000|n=II|num-b=8|num-a=10}}

Revision as of 17:36, 3 January 2008

Problem

Given that $z$ is a complex number such that $z+\frac 1z=2\cos 3^\circ$, find the least integer that is greater than $z^{2000}+\frac 1{z^{2000}}$.

Solution

Note that if z is on the unit circle in the complex plane, then Let $z = a + bi$ and we have $z = e^{i\theta}$ and $\frac 1z= e^{-i\theta}$

See also

2000 AIME II (ProblemsAnswer KeyResources)
Preceded by
Problem 8
Followed by
Problem 10
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
All AIME Problems and Solutions