such that 
for all real number 
and 
and 
on the plane such that 
is an equilateral . Let 
intersect 
and 
at 
and 
respectively and 
intersect 
and 
at 
and 
respectively .
,
on 
satisfies 
and 
.
be the point where the perpendicular from 
to line 
meets the angle bisector of 
.
holds.
be a positive integer such that 
.
.
over 
.
and 
Prove that
![\[\lfloor x \rfloor\]](http://latex.artofproblemsolving.com/d/3/f/d3f8facf62413e1f17c89b9c183a8735c2defe8b.png)
denote the greatest integer less than or equal to x . What is the sum of the squares of the real numbers x for which ![\[ x^2 - 20\lfloor x \rfloor + 19 = 0 \]](http://latex.artofproblemsolving.com/f/a/9/fa96f2d6217a16029e5f03499e0a83deffdfa28a.png)
Prove that
of the pizza, where 
is a positive integer. Find 
![\[\mathcal{P}(x) = x^{108}+x^{102}+x^{96}+2x^{54}+3x^{36}+4x^{24}+5x^{18}+6\]](http://latex.artofproblemsolving.com/e/b/2/eb28918359848dd07784a3c2c6a34b934743c016.png)
be 
.![\[\dfrac{r_1^6+r_2^6+\dots+r_{108}^6}{r_1^6r_2^6+r_1^6r_3^6+\dots+r_{107}^6r_{108}^6}\]](http://latex.artofproblemsolving.com/3/1/5/315341a7adf35bc04e40ee0685a011c9f7b76115.png)
without Newton Sums.
Is there an elegant way to prove this?
Y by Adventure10, Mango247
A circle inscribed into triangle 
touches side 
in a point 
. Segment 
is perpendicular to and has the same length as 
. Find a radius of a circle inscribed into triangle 
if 
cm, and the length of 
is 
cm shorter than the length of 
.
(O. Kukush, Kyiv)
touches side 
in a point 
. Segment 
is perpendicular to and has the same length as 
. Find a radius of a circle inscribed into triangle 
if 
cm, and the length of 
is 
cm shorter than the length of 
.(O. Kukush, Kyiv)
This post has been edited 1 time. Last edited by parmenides51, May 9, 2019, 5:24 PM
Reason: typos corrected thanks to member pentagon
Reason: typos corrected thanks to member pentagon
