Answer
See below
Work Step by Step
Given: $v_1=(1,-1,2)\\
v_2=(2,-1,3)$
Obtain $span\{ v_1,v_2\}=\{v \in R^3:v=av_1+bv_2 \forall a,b \in R\}\\
=\{v \in R^3:v=a(1,-1,2)+b(2,-1,3) \forall a,b \in R\}\\
=\{v \in R^3:V=(a+2b,-a-b,2a+3b) \forall a,b \in R\}$
Geometrically span $\{v_1,v_2\}$ is a plane through the origin determined by the given vectors $v_1$ and $v_2$
