Difference between revisions of "2006 Cyprus Seniors Provincial/2nd grade/Problems"
(problems) |
(→Problem 4) |
||
Line 29: | Line 29: | ||
[[ 2006 Cyprus Seniors Provincial/2nd grade/Problem 4|Solution]] | [[ 2006 Cyprus Seniors Provincial/2nd grade/Problem 4|Solution]] | ||
− | |||
== See also == | == See also == |
Revision as of 04:33, 12 November 2006
Problem 1
If with , prove that
i)
ii) .
Problem 2
Let $\Alpha, \Beta, \Gamma$ (Error compiling LaTeX. Unknown error_msg) be consecutive points on a straight line . We construct equilateral triangles $\Alpha\Beta\Delta$ (Error compiling LaTeX. Unknown error_msg) and $\Beta\Gamma\Epsilon$ (Error compiling LaTeX. Unknown error_msg) to the same side of .
a) Prove that $\angle\Alpha\Epsilon\Beta = \angle\Delta\Gamma\Beta$ (Error compiling LaTeX. Unknown error_msg)
b) If is the distance of form and is the distance of form $\Alpha\Gamma$ (Error compiling LaTeX. Unknown error_msg) prove that
$\frac{x_{1}}{x_{2}} = \frac{Area(\Alpha\Gamma\Delta)}{Area(\Alpha\Gamma\Epsilon)} = \frac{\Alpha\Beta}{\Beta\Gamma}$ (Error compiling LaTeX. Unknown error_msg).
Problem 3
If $\Alpha=\frac{1-cos\theta}{sin\theta}$ (Error compiling LaTeX. Unknown error_msg) and $\Beta=\frac{1-sin\theta}{cos\theta}$ (Error compiling LaTeX. Unknown error_msg), prove that $\frac{\Alpha^2}{(1+\Alpha^2)^2} + \frac{\Beta^2}{(1+\Beta^2)^2} = \frac{1}{4}$ (Error compiling LaTeX. Unknown error_msg).
Problem 4
Find all integers pairs (x,y) that verify at the same time the inequalities and .