Sarastro
Reputation
1,280
Next privilege 2,000 Rep.
 47m reviewed No Action Needed Continuity of a peculiar function Apr17 reviewed No Action Needed Categorical Banach space theory Apr15 reviewed No Action Needed Need help with calculating this product: Apr15 reviewed No Action Needed Recurrence Relation with Variable Coefficient Help Apr15 reviewed No Action Needed Study a math course on my own, suggestions? Apr7 reviewed Reviewed How do I prove that $\arccos(x) + \arccos(-x)=\pi$ when $x \in [-1,1]$? Apr7 reviewed No Action Needed Finding the area of the 4th triangle, given the areas of the other 3, and all the 4 form a rectangle Apr7 reviewed No Action Needed integrable bound for rational function with parameter Apr6 reviewed No Action Needed Is square root of n the same as log n for order notation of an algorithm Apr1 reviewed Reviewed Reverse engineering a Taylor expansion 2 Mar24 reviewed No Action Needed Sending a Space Module Into Orbit? Mar24 reviewed No Action Needed 1-D random walk weighted towards the origin Mar24 reviewed No Action Needed Finding minimum paths in Graph theory Mar24 reviewed Reviewed Using a fixed point theorem. Mar24 reviewed No Action Needed Transformation matrix for the reflecttion about the plane $x+y=0$ Mar17 reviewed No Action Needed Proof of 2^n deck of card, it will be reverse order performing n perfect in-shuffle. Mar14 comment Prove that if $N(z)$ is irreducible in $\Bbb{Z}$ then $z$ is irreducible in $\Bbb{Z}[\sqrt{\alpha}]$. In an integral domain $R$, $r,s\in R$ are associates iff $r=su$ for some unit $u\in R$. If $r$ divides $z$, $rs=z$ for some $s$. By my definition, if $z$ is irreducible, either $r$ or $s$ is a unit. So $r|z$ implies $r$ is a unit or $r$ is an associate of $z$. Mar14 comment Prove that if $N(z)$ is irreducible in $\Bbb{Z}$ then $z$ is irreducible in $\Bbb{Z}[\sqrt{\alpha}]$. For a ring $R$, $r\in R$ is a unit if $\exists s\in R$ such that $rs=sr=1$. An element in a ring is irreducible if it is not the product of two nonunits. Mar14 answered Prove that if $N(z)$ is irreducible in $\Bbb{Z}$ then $z$ is irreducible in $\Bbb{Z}[\sqrt{\alpha}]$. Mar13 reviewed No Action Needed Question about noise term in SDEs