Answer
$3y^{2}$ , $1$
Work Step by Step
$6y^{3}-3y^{2}+2y-1=$
...the first two terms:
$6y^{3}=2\cdot(3\cdot y\cdot y)\cdot y$
$-3y^{2}=-1\cdot(3\cdot y\cdot y)$
GCF: $3y^{2}$
...the last two terms.
$2y=2\cdot y$
$1=1$
GCF: $1$
Answer: $3y^{2}$ , $1$