Difference between revisions of "2006 Cyprus MO/Lyceum/Problem 2"

(Problem)
Line 14: Line 14:
  
 
==Solution==
 
==Solution==
{{solution}}
+
<math>K=((\sqrt{3}+1)^2-2^2)^2-(\sqrt{2})^2=(3+2\sqrt{3}+1-4)^2-(\sqrt{2})^2=10</math>
 +
 
 +
I'm not gonna go to sleep until someone fixes that.
  
 
==See also==
 
==See also==
 
{{CYMO box|year=2006|l=Lyceum|num-b=1|num-a=3}}
 
{{CYMO box|year=2006|l=Lyceum|num-b=1|num-a=3}}

Revision as of 21:12, 17 October 2007

Problem

The operation $\alpha * \beta$ is defined by $\alpha * \beta = \alpha^2 - \beta^2$ $\forall \alpha , \beta \in R$. The value of the expression $K = \left[\left(1+\sqrt{3}\right) * 2\right]*\sqrt{2}$ is

A. $3$

B. $0$

C. $\sqrt{3}$

D. $9$

E. $1$

Solution

$K=((\sqrt{3}+1)^2-2^2)^2-(\sqrt{2})^2=(3+2\sqrt{3}+1-4)^2-(\sqrt{2})^2=10$

I'm not gonna go to sleep until someone fixes that.

See also

2006 Cyprus MO, Lyceum (Problems)
Preceded by
Problem 1
Followed by
Problem 3
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