x^2+7x- 34.86
, ∀η ∈ Ν : 1·3+2·4+3·5+...+n(n+2)=(n(n+1)·(2n+7))/6
-x^3+50*x^2+2325*x-83500=0
(5r+4)(3r+2)+9(r+2)
12/(2^3/4)^-2+1
5x^2-750x+2000=0
2x-6y=12
x+3y=5
2(5 $\sqrt{2}$ )
28148=(204.2x)^2-(23691.8/x^2)
$log_{32}$ 2
