Hello,
To exist x≠0
if x>0 then
x+2/x>=3==>x²+2>=3x
==>x²-3x+2>=0
==>(x-2)(x-1)>=0 positive out of the roots
==> (x<=1 or x>=2) and x>0
==>(0<x<=1) or (x>=2)
else
x<0
x+2/x>=3==>x²+2<=3x
==>x²-3x+2<=0 negative betheen the roots
==>(1<=x<=2) and x<0 : no solution
end if
The standard deviation is the square root of the variance
so if the variance is 256, then the standard deviation is : sqrt 256 = 16 <==
Distributive property
a(b+c)+ab+ac
a(b-c)=ab-ac
(6z^2-4z+1)(8-3z)
move for nicety
(8-3z)(6z^2-4z+1)
distribute
8(6z^2-4z+1)-3z(6z^2-4z+1)=
48z^2-32z+8-18z^3+12z^2-3z=
-18z^3+48z^2+12z^2-32z-3z+8=
-18z^3+60z-35z+8
The answer is
(x+10)(x-3)
